If you're boring the block anyway, 235 aluminum pistons will be a drop-in fit with no other modifications. The wrist pin size and compression height are identical to 216 cast iron pistons. The bore would be 1/16" oversize, (0.0625") for a total of 224 cubic inches. The main advantage to using aluminum pistons will be less reciprocating weight- - - -quicker acceleration, and there will be less stress on those Babbit rod bearings, also.

Drop me a PM and I'll share a few other tricks an experienced engine man can incorporate into a basically stock rebuild without bumping the cost up significantly. Jon is right on the money about carburetion- - - -it's a lot easier to build a stovebolt engine for more torque than it is to chase those elusive high-RPM gremlins who are impossible to catch.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!