I just got a 1980 CJ7 with the 258 straight 6 with automatic transmission.1st question can someone tell me what transmission this most likely will be. It's not stamped anywhere. 2nd question the 258 has a blown head gasket. How hard would it be to put a GM 350 in the place of the 258. I already have a fresh 350 sitting on the engine stand. Could someone maybe tell me what all I would need to do to get the 350 to fit. Will the Transmission I have bolt up to the 350 or will I need to replace the Transmission as well. Thanks for any imput.