working on older stewart warner gauges, most gauges I have worked on have 3 connections
ignition 12volt
ground
sender
these gauges only have lugs for 2 connections the ignition and the sender. The ground looks to be picked up by the back bracket which has a copper tab which grounds the casing of the gauge. the 2 lugs are isolated from the bracket and the gauge by a nylon bushing.

does the back bracket pick up the ground from the alum dash plate? I didn't see a lug for a ground on the plate plus someone painted the back of the dash plate?

any thoughts??


Thanks

Some do use the bracket studs as grounds.