Finally found one picture, of a 62 Chevy car with them, and yes, that's what they are for. Tighten the screw down and they expand inside a hole. Once they are compressed, it looks like a grommet in the hole with the nut inside. But this voltage regulator fits a lot of years worth of vehicles, so I figure they are included in case they were to be used. But we ain't using them........
Thank you and bartamos.
