Project "Mirror"

After my mirror started to fall and jiggle with the bumps, I went to a salvage yard and got me a nice compase/temp/dimming mirror out of a 2000 Chevy Truck. I got the wireing information from Chevy and have found out that all the electronics for this mirror are in the mirror itself. I got the air temp sensor and pig tails to wire it up. All I need to know is where is the reverse light switch on a 95 Transport? I beleive it is on the transmission, however I would like to keep my splicing inside the dash and away from the outside elements.

Yes the reverse light switch to tell the mirror not to dim when I back up. Other connections include run/start power (simple), ground(simpler) and two wires for air temp sensor. Simple project! Just got to find that wire and some time:)