Since a 216/235/261 bellhousing will bolt onto a GMC engine, and the starters will interchange, it might be possible to redrilll a Chevy flywheel to fit the GMC crankshaft bolt pattern. Is your crankshaft the 4 bolt or 6 bolt type? I have both types of flywheel on hand (Chevy and GMC). I can make some comparison measurements if you like.
Jerry


"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
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