My wife's 02 Excursion has heated seats and the button is on the side. (I'm always bumping it "on" when I get in and fry my in the summer)! The thing to consider is if there is any factory wiring under you seats now or if you will need to make your own harness.

 

the button for my 07 is right on the side of the seat like everyone else's. i always made fun of the people i knew who had heated seats til i bought this truck last week. man its nice to have on a cold morning here in mass