I don't think there is a thread to provide answers of what suspension fits what model cars, out of different models, so I'll start with one I just saw. Please only put something in here that you know is 100% legit.
If there is another thread, then I've missed it.. oops!
Mods, please sticky this into the Mega FAQ thread - http://clubsub.org.nz/forum/showthread.php?46299-ClubSub-Technical-MEGA-FAQ-*Beta*
Suspension from a BD Legacy, fits into a BC Legacy, with a swap of the rear tophats.