Engine swap question

Trying to put the engine from a 78 Jeep manual transmission (not sure exactly what it came out of) into a 1983 AMC Eagle automatic. Engines appear to be identical I have: removed the clutch and flywheel from the new engine. I installed the flex plate from the old engine, but can't figure out how to install the torque converter from the old engine. It won't fit into the bellhousing. Someone told me I need a special tool to put it in? Done several engine swaps before and I've never had this problem, any advice would be appreciated.

What do you mean 'won't fit'? Didn't it come out of that transmission.
Before the engine is bolted to the trans, you slide the torque converter neck into the transas far as it will go. You then need to rotate the converter up to half a turn while pushing gently. The converter will rotate a bit then slide about another half inch into the trans. Then attach the engine.