BMW e36 interior

Does anybody know if it is easy to replace leather inserts on an e36 bmw m3, front door cards inserts and rear inserts as well. I have silver grey leather and want to go to black. I have found some black leather interior but the doors cards are black with black inserts and I need grey with black inserts. So I plan to keep my grey door cards and replace the silver grey insert with the black from what I have bought.

Any help will be appreciated.