CAN, PID, Mecanums

[Ceebs03]

My team is using mecanums and CAN, and I want to use the KOP encoders and the PID on the jags to make sure the wheels spin the right speed.

I believe to do this I need to open each motor individually in speed mode, set the PID values, and then plug them in to a four motor drive of "existing motors"

My questions are:
Do I need to change the holonomic drive VI to make it work with speed mode?

Do I need to use speed mode to do this, or is there a way to do it with Percent
VBus (which should work unmodified with the holonomic drive VI, right?)?

I need to "tune" my PID right? what is the recommended method for doing this? I know trial and error is common, do I need to test with the whole robot, or can I use BDC-COMM?