D150 wiring issues, help!

Extra braded ground strap from engine block to fire wall. Clean battery posts. Clean ground cable where it bolts to engine block.

Good Grounds for starters.

Now go into the fuse block in the glove box and when the gauges are acting up take your fingers and feel for heat at each fuse. Take the fuses out one at a time and polish up the ends of them with a scotch brite pad, same with the U shaped fuse holders. If you have one warm or hot fuse that is probably your problem.

Funny you should ask, was into my '76 D100 wiring this morining for a little back feed to one turn indicator light.

Traced out the wiring, then went to the fuse block and found a warm fuse, polished it up and put in a new right front Turn Signal Bulb.

All better now, good to go again !