To remove the handles you firstly need to open the suitcase and locate the internal screws that secure the handles to the frame of the luggage. Then use a crosshead screwdriver to detach the handles from the luggage and attach the new handles.
To remove the locks, you first must locate the screws that are securing the locks into the luggage, from there you need to loosen the screws and detach the locks from the luggage. Now attach your new locks and set your new code.