Hello there I am new to the sight so please bear with me. I recently swapped out my automatic in my 83 gmc sierra classic to a muncie 4 speed that I took out of an 83 gmc sierra. Both have 350 crate motors. I've got the tranni installed but when I try to start it the starter dosen't fully engage the flywheel and it chatters. My battery is fine and I am using a charger/booster just to make sure. I've tried about every combination of shims, didnt help. The motor will turn over by hand fine so its not an engine issue. I am using the starter that came out of the donor truck which is also the same as the starter in my truck. The flywheel came of a gmc van and is 268 tooth count which is the same as both trucks. My truck has an external balance and the donor truck has an internal balance camshaft. Hence the vans flywheel which matched up!! I'm stumpped!! My mechanic friend is getting me the starter out of the van just to see if its different but I don't think it is. Hopping for some thoughts. Thanks!!!!!