I changed the screw/bolt to a steel one with washers to ensure more contact. No luck/no start.You have a welder, so hit all the nutserts with enough to make them part of the chassis electrically.
Stainless rusts everything else that's not the same stainless, so that could easily be it.
I also verified that the fuel pump runs while I'm trying to start the car. I also have verified fuel pressure.