Changing out seats
 

I have an 02 Boxster S with fully functioning electric seats and am buying another car exactly like it with much lower mileage and PSM and will need to trade seats. Can I switch seats with no up/down and lumbar for fully electric ones?

sure why not, all the wiring is the same

The only thing (and I'm not 100% sure) if you have the seats with Memory buttons, they will likely need to be activated or coded with the PIWIS as they tye in with the on board computer system. If neither car has the memory seats you should be fine.