R32 runs 100% to the rear then splits up to 50% to the front when needed.
R33 and R34 run 95% rear 5% front, the splits up to 50% to the front when needed.
There is a procedure in the workshop manual for putting in to RWD (in the 33GTR manual, I use the same process on my Stagea).
The manual states either drop the front prop shaft OR, disconnect the airbleed plug (inside the drivers kick panel), start car and push brake pedal 5 times, 4WD light starts flashing to tell you you're in RWD mode.
Have a good search, I have posted this up quite a few times and regardless of what anyone says, myself and others over here have PROVEN that it works.
It works so well that I've actually put a switch in my centre console and drive around every day in RWD.