Well, technically they're supposed to be "world class T5's" in the turbo cars but the input shaft is still the small 4 cylinder size. You can use it but you're gonna have to get the Mazda truck pilot bearing (forget the part number) to make it fit into the back of the 302. I *think* the internals are the same as the V8 T5 but don't quote me.
The trans has a 3.97:1 first gear so, it will wind up very quickly. If you blink you will have hit the redline in first gear before you know it. It also has a lower torque limit spec, 235 Ft/Lb, so it may break easier than a V8 T5. The pilot shaft is smaller, so you will need a different pilot bearing. The pilot bearing you need is for a Ford Ranger diesel from AutoZone part #14672 - hope this helps!!!
is the clutch the same? all i need is the pilot bearing? it isn't going to be permanent, just so I can drive my stang until the correct t5 can get rebuilt
The clutch is the same. The difference is the inner diameter of the pilot bearing on the V8 is larger than the tip of the 4cyl T5 input shaft. The bearing you need is smaller in the center while still being the right size to fit into the back of the crank.
I have a friend who swears by 4cyl tranies. He's used them in pretty much every Mustang he's owned. Granted, none of them have been faster than 13s but he's beat the piss out of them and they never broke on him.