I have a 1984 720 2WD that's an electrical nightmare at the moment. I bought it a few months ago for a daily driver/project and it's started out mostly as more of a project the more I look into it's problems.
The headlight switch works only if it's twisted in a certain way while holding the outer cover on the column
The radio seems to be a replacement of a replacement of a replacement... and the last guy who did it just used a couple of terminals for the ground to the whole radio
The battery charges... most of the time... (possibly just a bad alternator)
I have a fuse that routinely blows which controls the turn signals, indicator lights, and some other stuff. The only indication I get it when the dash lights are still on, the truck is still running fine, but the battery light is on and the signals don't work anymore. While extremely disconcerting, I don't think it's effecting much with the truck running or operating other than being a pain to figure out what part is wired wrong.
One of the fuse slots in the block shows signs of having been shorted out by something. I assume, after that, someone took out the old fuse (if anything was left) and changed the wiring around in order to 'solve the problem'.
Right now, my plan is to not necessarily replace parts but to make/build a switch module to control the basics (headlights, start, etc). If I follow that plan though, it means that I'd have to tear apart the dash in order to do that; so, for the time being, help of any sort would be greatly appreciated to fix or otherwise get the truck into a more reliable shape.