170 vs. 225 Swap

You can swap the 71 225 engine into the 63 car easily. You need to get a crankshaft adapter bushing (from @slant six on this site, and inexpensive). Need a 68/later flexplate. Use the engine bracket/mounts, carb/linkage from the 63. Also need to swap the oil pan, and pickup. Ignition depends on what you want. Can use the 63 points distributer/system, or use the 71 distributer.

EDIT: Just a FYI. the reason for using the early carb is because of the linkage hookup. However the early carb for the 170 (if it is original) is smaller than the carb for the 225.