rear view mirror help

I have a 1998 silverado and I would like to upgrade my rear view mirror, preferably to one with not only compass but temp. Can anyone tell me how this works. I found some silverado mirrors on ebay with temp. and compass, do I just buy one of those and wire it in? Also, is the temperature sensor usually seperate than the mirror itself. Any help would be greatly appreciated.

thanks
justin

also, any help on where I can find a good mirror would also help. thanks

You may have to run the wiring yourself. Some trucks have the wiring even if they don't have the option the wiring is there for, others don't have it. I believe the temp sensor will not be in the truck, you'll probably have to buy that. The compass and electronics are probably inside the mirror.