Norbie, I believe that there is a pressure plate that cna marry the two, I think that it is to suit the 4Y but you will need to drill the locating pins in the flywheel (different PCD as you are well aware, and the clutch will need to be stepped at new dia duh).
Correct me if I am wrong, but the disc that you are talking about (from JZ A80) is 236mm?
I will hunt through some info that I have at work and I will let you know the outcome.