How does the transmission couple up to the drive axle? Since it appears there's already been a swap made to a non-original engine, have you considered upgrading the powertrain to a more modern engine/trans package? How about a 292-Turbo 400 setup to eliminate fighting with the crash box transmission? You would have more HP and torque than the 261, and a "shiftless" powertrain.
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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