that's the correct switch, and the dome light will work as advertised using it, providing everything else is good - the rotary switch on the front of the light switch provides the ground ["GRD" with the copper spring contact that goes under the plastic doobie] via the variable resistance in it, from open to full ground - the "S&D" provides the + all the time - you need 2 wires to the dome light from those 2 terminals, GRD and D - you could also put a toggle on the light rigged to give a ground to bypass the dash switch if desired

Bill

Moved over to the Passing Lane

"When we tug a single thing in nature, we find it attached to the rest of the world" ~ John Muir
"When we tug a single thing on an old truck, we find it falls off" ~ me
Some TF series details & TF heater pics