Swapping zt electronics car-to-car

[YHT]

I have a project which has only one key that doesn't remotely operate the drivers door; you have to put the key in the drivers lock and turn twice to open all the doors. Its starts OK.
I have a donor vehicle with 2 keys on which the remote and everything else works. What would I have to transfer over between the donor and the recipient to get full functionality from donor to recipient (and how to do it!) (and is it difficult)