Oldscooltoys

Ok so I traded for a 1985 2wd pickup. The guy had the motor out and in the bed of the truck and it was at night when I had the chance to go see it. The PO said it had a blown head gasket. So I have it at my house borrowed a cherry picker and wanted to drop the motor in as quick as posssible so I didn have the neighbors picker for too long. Needless to say I rushed and didn check for a lot of stuff. The oil pan is a 4wd pan. So I'm waiting for the 2wd pan to come in tomorrow. The clutch and pressure plate along with the flywheel were in the bed of the truck and was a little rusted. I'm moving to Hawaii to be closer to family so I'm just wanting it to atleast run. But I figured ah I'll get a new clutch kit. So I give the flywheel a quick clean up to get rid of the surface rust and bolt it up. Then I check the old pressure plate vs the new kit. The clutches are the same but the pressure plate that was in the bed of the truck is a little bit larger. The distance from the flange where it bolts to the flywheel to the end where the theowout bearing presses. So the new kit that I got for a 1985 2wd is smaller. What am I missing here? Or what do I need to do. I have the head gasket changed (hoping that's all that was wrong) looked like between cylinder one and two was the leak and I'm waiting on the oil pan to get here and I've already bolted the trans and stuff up and now I'm pulling it back out. Trans is a 91 by the way. But I can't get them separated. It's stuck. Is it cause the pressure plate?