Nissan Micra Vibe 1L 1997. Changing Door Locks.

I'm looking for some advice on my car!
I have a Nissan Micra Vibe 1L 1997, I have no central locking and my driver side door lock is beginning to become stiff. I have already tried WD40 and GT85 but that only lasts a small while and I don't really want to carry that everywhere I go! :(

I have had the door card off and everything seems okay. I have brought new door locks for the car as I've come to the conclusion that both the discs in the lock and cuts on the key have become so worn due to their age and constant use. To save money I would have just swapped the passenger side door lock with the drivers side door lock but obviously they are handed.

The advise I need is how to fit these new locks. I've been assured they are the correct ones and would just like a small tutorial on how to fit them!