Wow, you must enjoy a challenge if you want to do this
Have you got a VIDA/DICE diagnostic tool ?
If not, you might need this tool after replacing the seats to check all the components are connected and operational. And even before you replace anything, VIDA should help you understand which components need installing, e.g. a module responsible for managing electronic seats.
Maybe you will need to install or replace some wiring ? Again, VIDA might help you determine this.
Good luck.