Unless the harmonics have been measured with a spectrum analyser, you won't know if it's legal or not. The fact someone may or may not have had a problem isn't that much of a good guide. An antenna tuner will certainly help.....Or see if you hear from the Famous Candy Company.....but it's a bit late then...
One possibility is to use a half wave filter for each band - then the match is relatively unimportant.
So what did Twelve-Year-Old Novice Builder do in 1969, lacking a spectrum analy(s/z)er? Or has the FCC become more stringent about harmonics? My general impression is if anything there is less of an issue because (a) TVI is less of a problem now that TV Band I and III have been largely vacated of TV, and (2) the FCC seems to have fewer enforcement resources than in the days of yore (not that this is any excuse to break the rules).
I like the idea of a halfwave filter. I've always been intrigued by this one, which is two halfwave filters (40m and 80m) mounted inside a coffee can. It comes from "Understanding Amateur Radio," 1963 edition. I have a whole pile of those miniductors that I could use for this:
I've always mounted these variable caps by the two front screws and have on occasion created the third at the 12:00 o'clock position by drilling and tapping a new 4-40 screw hole. However, you found you had a problem and solved it in a remarkable way. I studied your method of "hole layout" and compliment you on it.
Al (K8AXW): Thanks for the compliments. I don't have thread taps in my workshop and it's a good 40 years since the last time I tapped a thread! There were also some additional holes in the front of that capacitor, but they weren't tapped, so I would have had to insert a nut between the plates and the armature. But the nut would probably have been too thick and would have caught on the plates. BTW all the screws are #6.
Oh, don't ever get put off by any comments or suggestions on "what you should have done" Martin. This is just another version of "looking over one's shoulder" with the almost insatiable desire to grab it and doing yourself!
Don't worry, I won't be put off. Nearly all of the comments include useful information and tips to do things better. Furthermore, everyone knows I'm a relative beginner and they won't know what I already know, and what I don't already know. (Yeech, I'm sounding like Donald Rumsfeld.)