You can bolt in the 360 with the following notes.....You'll need a bushing for the end of the crank for the small button converter (I think Mancini has them); A custom 360 converter for your trans or the B&M flex plate for your existing converter; motor mount brackets that will fit the 360 block and your K-member (Schumacher or modify your 273 ones); a 360 car oil pan, and a custom exhaust system. Most everything else should transfer over from your 273. If it's a true '65 model, it would not have a push button transmission. '65's were still cable shift but either on the column or the floor.