I also use a soldering gun for nearly all my work, and that includes a good deal of 259s.  I have both sizes, and regularly use the smaller 100 watt gun.  The 250 watt gun is only used once in a while.  As a matter of fact, the only iron I have is a small Antex 18 W model that I use for circuit board work.

Soldering is an art, and soldering with a soldering gun is an art onto itself.  It can be done if done correctly.  Not to start an argument, but I was once told that a soldering iron is a brute force tool while a soldering gun is a 'finesse' tool.  ;-)  73!

I agree, you have to get hold of the right supply, but if you get a high capacity (400-500 watt) supply, this little cheapie project will work.  I've gotten a 400 watt supply, wired a wire wound resistor (47 ohms, if I remember) onto the 5 volt section and have gotten fifteen amps out of the 12 volt section before adjusting the supply to get move voltage from it.  I ended up with about 13.4 volts at 12 amps from my $20 investment.

Since this is a rebuilding/reconfiguring project, it is meant more as an educational project than a practical, everyday use project.  It can be done BUT (you just had to know that was coming) I would not recommend such a supply as the primary supply for a radio.  I use it with a standby VHF rig, there isn't any noise problems to speak of, and it isn't used every day.  Mind you, I wouldn't use this supply with a HF rig except to just listen to the bands, but it works fine powering a 40 watt VHF rig for both transmitting and receiving.

"One thing I haven't taken into consideration. I know the land I'm on is not "good ground"........I know the center fed doublet is far more independent of quality of ground than anything else. Since also, half of it is the ground. Would you say, probably my best bet is to feed a center fed doublet with balanced line?"

I think you've answered your own question.  A center fed doublet fed by the balanced feed output of your matchbox may be your best--and safest--bet.  Minimal RF and no problems from the 'bad ground'.  73!

Another way to eliminate that noise from the plug wires is to replace them with higher quality aftermarket plug wires.  Include replacing the distributor cap when you do and you may well get rid of all the ignition noise.  In addition to getting rid of the noise, you'll probably increase fuel economy too!  

It has been my experience that the original equipment spec parts on a lot of cars are much inferior to aftermarket parts, especially if the better grade aftermarket parts are used.  

One sure way to make those sheet metal screws fall out is to begin by drilling too big a hole.  The Self locking self tapping screws have a drill tip right on the end of the screw--unless the sheet metal is really thin or the wrong drill driver bit is used and the screw 'rocks' when the hole is being drilled, the self tapping screws work well.

Now what is that old saying......Oh, yes!  Use the right tool (bit) for the job.  The job will get done faster and better.  :-)  73!

One point from the National Electrical Codes:  The wire colors used should be different for ease in identifying the side of the 240 v line you are using--you should have black for one 'hot' side, red for the other 'hot' side, and green for the ground.  Since it sounds like you already have them in place, get a roll of red electrical tape and identify one of your black wires using the tape.  Be sure you identify the ends of the same wire.  Other than that, you sound like your ready to go!  Good luck!

Concerning crimped on connectors vs. soldered on connectors:

The only thing to watch for when using crimped type 'co-ax' connectors is to not crimp them on so hard that the cable is deformed or 'squashed'.  If the cable is squashed too much the cable impedance changes with an end result of lessening the power reaching the antenna.

As for soldered connectors not being as reliable as crimped connectors, I've yet to find a properly soldered connection on any type wiring to be not reliable.  The reason aircraft require crimped connectors is due to FAA regulations.  It takes skill and practice to properly solder any type connector to a wire or cable--and be sure the connection is a good one--while just about anybody can make a good crimp connection using the proper tools.  The FAA realized this and that is why they mandated crimp connectors on aircraft wiring.

To go a little further, and this even includes co-ax connections but is especially true of single wire connections, it is better to crimp AND solder connections.  The crimping of the connector provides a good mechanical connection and the soldering of the wire/connector joint afterwards provides an excellent electrical connection.  Soldering the joint afterwards 'locks' the joint together, and also prevents corrosion from starting between the wire and the connector.

I've also used crimp on style connectors on co-ax cables.  I've always soldered the tip of any PL-259 connector just to make sure the center conductor doesn't pull free and cause intermittant problems.

The vehicle radio antenna feed through is visible from inside the vehicle only, the view from the engine compartment side is blocked by the condenser core.  The wires will be able to be routed and pulled through with a snake.  If you aren't sure of your ability, however, it makes sense to find another way.  Sorry I couldn't be more helpful.  Good luck!

When you say no new holes allowed, I'll assume you mean through sheet metal.  With that being said, look at the firewall on the passenger side, up behind the dash.  Find the grommet that seals the hole where the antenna cable runs through, make a hole in the grommet (there's usually plenty of room since the cable goes through at an angle) and feed your power wires through there.  When the wires are removed, the rubber grommet will snap back to its former position, you'll never see the hole unless you look for it.

You can get the co-ax through the rear area by routing it under the carpeting, through a side compartment in the rear of the SUV and past the rear hatch gasket.  A little tough to run, but when its removed you'll never know it was there.

Good luck and 73!  

In a lot of cases, a fender mount was used for VHF frequencies on trucks, the trunk was the preferred location for patrol cars.  The only thing the fender mount will do is to skew the radiation pattern somewhat vs. a center roof mount.  The cab roof of a pickup isn't large enough for a proper VHF ground plane anyway.  

I've even seen a 2 meter antenna mounted in the center of a pickup truck hood!  Granted, the truck owner was a few french fries short of a happy meal, but the location worked, and worked well.  No excessive RF, either.

Anyway, if you have trouble with a mount next to the CB antenna, the front fender may be your only other option.  Good luck!

The reason Hi-Gain states no closer than 5 feet above ground is because of reactance between the antenna and the ground.  If you do mount the antenna that close to the ground, although it will be useable, you won't get any sort of range out of it when transmitting--to try to explain it simply, most of the effective power will be 'shorted' directly to ground.

Why not get a five to ten foot section of pipe and fabricate a foldover mount so you can 'hide' the antenna when it isn't being used.  You'll have a much better antenna system and will be much happier with it.

Good luck and 73.

Check to see if there are any clubs around where you'll be on field day.  One place to do this is on the ARRL website--although they list only the affiliated clubs, you still may find one close to you.  Depending on the setup the club uses, you may even be able to operate the rigs that will be there.

The other thing you'll find there is a group of people who are friendly and will help you, sometimes just by answering your questions.  Be sure you bring a small supply of food and drink for yourselves--you may end up staying the better part of the day.

Good luck and remember, HAVE FUN!!  73!

How about mounting on the front fender or the rear side bed edge?  Both locations will get the VHF antenna out of the pattern of the CB antenna and will minimize the potential interference between radios.

There are hams out there who would be glad to lend a hand, its just that they are fewer of them than in years past.  Unfortunately, the realities of todays world have cut down on the time people have to spend on hobbies, and ham radio is no exception.  Some of us find we have to work two jobs just to make sure we have the means to live life--never mind have the extra time for a hobby.  

I agree with the idea of joining a club, that is the best place you may find a willing elmer.  Good luck and 73.

Forget about a glass mount antenna--those are 'compromise' antennas, the compromise being a loss in signal strength.  Although they work, they will not work as well as a properly mounted antenna which is directly connected to the co-ax and the car body.  If drilling holes is a problem (the XYL objects, for instance) there are mounts that clamp over the trunk lid edge or are screwed to the inner metal of the trunk deck opening, just under the rubber weatherseal.  Use a little silicone sealer on those attachment points and there won't be any leaks.