olblu, a momentary switch is spring loaded to return to either the on or off position, depending on the switch. That's why they're "momentary."
I have a set of late '40s/early '50s Guide B50 backup lights from a GM car that will go on the panel when I get to that point. They are round with glass "beehive" lenses. Look around on eBay for early backup lights - some of my favorites were old Studebaker lights with "beehive" lenses and four littel rocket fins molded into the lens, but they were always expensive. The oval backup lights from an early '50s Pontiac would probably look nice, too.
