Heated seat question

I have a Spyder w/o heated seats. Looking at the Euospares diagram, it seems like the heating unit is a pad that sits under the leather and plugs in and a switch in the seat. I assume the wiring harness is already there. Has anyone ever taken apart the seat unit or tried to install this after the fact? I could buy the heater assembly and switch but worry about destroying the leather when I install it. Anyone?
(Cold butt in NY)