How to deal with stripped out holes on Firewall
I replace the sheet metal screws with machine screws, washers and nylon lock nuts.
They always stay and I think it makes a more reliable ground for things that need or could use it.
For stuff that the grounding of it is critical gets a star type lock washer between it and the body.
I like the ones with the bite sections on the inside so they don't look to strange when used between things.