Very Confused!

The ground comment from your mech:

There may or may not be more to that. It might be that the body is not really well grounded to the battery. One way to insure this (battery main cable should be grounded to block) is to buy a 1 ft--1 1/2ft Ford style "starter" cable (eyelet to eyelet) and ground it to the engine block, and to the body. The master cylinder bolts work for that, and on a V8, the same holes are on the rear of the driver's head, which are on the front of the pass head. So you can find a short bolt and connect that cable there

Be sure the paint is scraped from the firewall for the VR mounting, that the bolts are not stripped, and you might scare up a couple of star washers. Does not matter much if they are internal or external star

Then we can go from there

I may not be here much, I am fighting a house fire situation.