In software, I use Tunercat and TunerPro RT, you could also do it in Kalmaker at twice the cost. You have to delete and reburn the memcal with the modified tune. All the sensors other than the cam are the same, the ECU will be fine. You may have to shorten the coolant sensor wiring if it is an old VN motor with the rear thermostat, and the gauge too. MAP, TPS, IAT, Coolant all the same, it might be worth using the DFI and coils off the existing VR engine as I don't have the wiring diagram here to compare them and I think the cam/crank wiring goes through the DFI to the ECU.
Joel