HELP 76 dart gas an temp gauges wont work!!!

turns out the in dash regulator around here is 37 at auto zone and 54 at napa.
Sorry, I was thinking of the one under the hood when you said "electro-mechanical". The 5V Vreg on the dash cluster is expensive, if you get a factory mechanical type. Many people install an electronic one, which is less expensive and much better. I got one on ebay for ~$25, also check IVR. Not like the original, it is a small circuit board you velcro to the cluster.

I agree that fixing traces on these boards is easy. These are old, hand-drawn one-sided wiring boards with wide traces, nothing like fixing a computer motherboard. You can get replacement boards for many models, but ~$100 and a lot of work resoldering components. No need for that since most are repairable.