Torque Converter hitting crankshaft

[mustang51p]

I am trying to mate a TH350 from a K-5 to an engine (305) from a 83 Camaro. I got the proper 153 tooth flexplate bolted up, with the TH350 bolt holes. I went to mate the 2 and nub on the torque converter is hitting the end of the crankshaft, not allowing the 2 to mate. Is it that I need a different torque converter or is it that I need an adaptor of some sort. I was of the understanding the engine and tranmission should go right together. Any help would be greatly apprecaited.
Thanks
Sean