I'm curious where you're getting the turbo pressure plate will bind in the housing. All of the information I'm reading says it'll work as long as it's mated to the correct flywheel. You started the thread, which makes me think you may have tried it without success.
From z31.com:
"The second strongest Z31 manual transmission is the FS5W71C. This transmission is used in the 240SX, 180SX, Silvia, etc. A few people who have blown up their FS5R90As have swapped to this transmission and not had problems."
Yes. I tried it. It binds up. So I'll say it for the 3rd time use the correct parts for your application.
