318 to 360
For the 360 engine balance get a flexplate that is weighted for the 360. B&M and a few other vendors have them. About $50-80 This way you can use your current torque convertor.
Drivers side motor mount is different. I've heard you can get them at a local parts house for spool mount set ups. Might check it out.
Most everything else will bolt up. The exhaust really needs some detail as the 318 ports on your exhaust manifold might be a bit smaller than the 360 heads.