You don't have to uninstall BIAB, and in fact, I would leave the program where it is on your C drive, and just move the RealTracks and RealDrums. MOVE = Copy, test, then delete. To make this work, you have to go into Preferences, RealTracks and specify the Custom location. Same for RealDrums, although that folder is far smaller.
Hmmm, so there's no penalty in speed or performance if the program is on one drive and the RealTracks/RealDrums are on another?
I would have thought that you'd want to minimize disk jumping/thrashing or is everything needed dumped into memory?