I’m swapping out to Autometer procomp boost gauge and for some reason the bulb holder does not illuminate. The old gauge I replaced had 2 blade terminals a 12volt and a ground. The procomp I am installing doesn’t have any terminals. It has a standard hole that the bulb holder terminal fits in. Bottom line, I’m sure the bulb terminal is good because it was used with a previous gauge. See pics below. Does it have something to do with the new one not having a terminal blade for a ground??