It's possible, like the slight stroke increase the "Cadillac 261" article that was published here some time ago using 292 6 cylinder rods, but most machinists are unwilling to modify a grinding wheel to the width required to do that job. Can't say I blame them, since those wheels cost several hundred dollars and it takes a major teardown of their grinding machine to change wheels. Most of those guys are in business to make a profit, not accommodate some hotrodder's off the wall ideas! Very few stovebolt builders are willing to go out and buy a crankshaft grinder (like I did) just to tinker with changing strokes. I'm so goofy I actually bought TWO of those machines!
LOL!
Jerry