You should speak with the cam grinder before you make a purchase. The power band of the motor (cam selection) needs to work with your 3500 converter. If they do not work together, you will not optimize the package and you may be disappointed. They will need to know a bunch of facts to get you the right cam. Compression (measured and calculated, not guessed)and other stuff will affect your choice.

You'll need a hand full of thick washers to shim the 318 engine mount to fit the 360 block. Measure carefully so you don't crack an ear bolting things down.