Swapping seats out in an early W163 (ML320)
 

I have a 1998 ML320 with manual cloth seats and am wondering whether I can swap in electric heated leather seats from a 2000 ML320 parts car.

My question is this: Is the wiring for the heated and electric seats already in the car even though it has manual seats? I'm wondering how complicated swapping the seats would be.

Thank you in advance for your insights here. I'm new to the W163 (and enjoying it immensely).

Douglas