6HP's comments are pretty spot on.
I can add, I've had a much-modified R75 for a lonnng time that gets a lot of use, and one of the earliest of many mods was the Pete G attenuation mod. But before I did that I did just the jumper mod, and found some difference from stock (a few dB maybe) over LW/MW in my fairly low noise environment, making the effort worthwhile enough. Then some months later I found the skill and motivation to do the full Pete G mod and I can tell you it does make a noticeable difference from just the jumper mod.
BUT, all that said, I honestly think (at least in my relatively calm noise situation) the effect of the full Pete G mod is not all that distinguishable from the effect of just the jumper mod and a decent antenna and the R75's built in preamps. Depending on your noise floor, you may not notice that much difference either.
An aside, I completely agree that one should NOT have to rebuild a commercial receiver to have it work at its best, and if surface mount soldering and so on is not your thing I totally get it. But for me, one of the reasons I became a fan of the R75 early on is because it is so eminently modifiable, and I enjoy tinkering and improving and customizing, with all the filters and audio quality mods and so on. I even reversed the polarization of the display and its smd LED coloration so it's been a Drake R8-like display (light green characters on dark green background) for the last decade or so.
This link should lead to an ImBB image of it:
https://ibb.co/cb74XWPIt's an interesting look anyway.

Best --
Mike
N0TLD