2003+ P71 Replacing standard with powered seats.

Looking at last gen P71. Torn between the luxury of the GM and the performance of the P71. I would like to get a P71 with a powered driver seat and replace driver plus passenger with GM full power leather seats. Anyone have a guide? Read the thread for the 2001 but not relevant to the 03+. A couple questionions:

It looks like the rails are the same for powered and standard seats. Correct or incorrect?

If I install on a prepowered driver seat can I splice it for the passenger seat?

If no power is there how hard is the install of the harness? Local pick and pull of a GM unit?

And last...on a medium power supercharger will the P71 auto tranny need any upgrades?

Thanks for help. Looking forward to be a last gen Panther platform owner.

The wiring could be there for the drivers seat, you'll have to look under the seat and behind the door panel, I believe all cars got the wiring for power drivers seat but not the controls if not ordered with it.
The passenger seat shouldn't have anything for the power seat, you can move the power seat to the manual track/frame or track down the wiring for it and run your own wires.
It's generally easier to upgrade handling/performance for a non-P71 then to upgrade to a better interior on a P71.