So I thought I had done the reading, and I've went back and done more reading and searching, but I can't quite seem to figure out what isn't right.
Car. 240z, 4/'71 manufacture date with STI 3.9 diff installed. Stock clutch and flywheel.
New Transmission: '83zx n/a 5 speed installed with matching throwout bearing a fork. New ZX slave cylinder.
When bolted up the fork is all the way forward with no movement and the bearing is pressed aginst the pressure plate and there is not enough clearance to mount the slave cylinder. See picture.
I'm not sure if the 5 speed transmission was out of a coupe or 2+2, I've sent the guy I got if from a message to find out. I noticed this detail in my readings: A Zcar 5-speed will fit on any year Z block and any year L28 clutch can be used. But the throwout bearing "collar" must match the style of the flywheel (coupe or 2+2). In other words, if you have a 2+2 flywheel, you need to change the throwout collar to a 2+2 version. A coupe flywheel uses a coupe collar.
Is this where I went wrong perhaps?