The vin does not really need to be loaded, but it can be if you want.
You are also going to need to worry about the trans cooler lines, they are going to be different, I suggest putting the 97 radiator in the GT as it is pretty easy to do, and anything else is pretty tough.
Also, the 2002 GTP pcm is going to be looking for a 99-03 throttle body... Either tune in the correct throttle body settings, or get a 99-03 throttle body.
I suggest AGAINST putting the boost solenoid control in, and to just run the BBV in manual mode. The map sensor wiring will need to be swapped, but that is just 3 wires. You can avoid changing the wiring by using a series3 2bar map, as it plugs into the stock GT harness.
also, I have found that 02 PCM's do not like to operate the older transmissions. I do not have much specific information on this yet, but I have been having problems with it as of late.