I built up a 2-sheave damper for a 235, using a new 6" diameter balancer for an early small block V8 (265/283/327, etc.) By inverting a 2-sheave pulley for a big block engine over the 6" damper, the fit is very close. It is necessary to shorten the balancer hub about 1/4" and machine the OD of the hub back a similar distance to prevent oil seal damage. It's not an easy fix, but the engine ends up with a brand new balancer, not a recycled or repaired 50-something year old one.
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!