I would not call a cigar/cigarette lighter a 'rheostat in drag'; maybe a "controlled short". My guess is that there is a difference between a 6v lighter-button and a 12v lighter button.
Justin,
What year truck are you going to put this in? Do you want it to look like an original GM accessory lighter?
I bought ligher buttons several years ago (Chevy Duty, Jim Carter, Truck Shop) and most of the vendors then specified 6v or 12v. They do not seem to specify voltage anymore (or they specify 12v).
Tim
