65 A Bodie fuel & temp gauge problems

Things to do while it is out:

Loosen/ tighten all screws to "scrub" the copper clean, or remove them and use an eraser or some very fine sandpaper, like 500g, as well as the lamp socket terminals. Examine and clean lamp sockets, bend the little contact ears for tight contact. Loosen/ tighten the stud nuts of the gauges for same reason.

Examine the board connector pins for any looseness and or corrosion. Solder them if any question as to contact.

On that note, you should consider getting some rosin flux, either liquid or paste, for soldering. DO NOT use paste flux bought from a welding or plumbing store, it is almost always acid. I've bought paste flux on ebay called SIR which does not seem too bad. Always use radio/ electronics rosin core solder and not acid core plumbing solder. I still like to use lead solder instead of "lead free." It is higher temp, and most of it which you can access will be for plumbing.