I also bought the 2 groove pulley from Buffalo. I'm building a 261 and had it balanced w/ the crank, flywheel, and gear as an assembly. Easy to do (or have done) when the engine hasn't been assembled.

1962 Fleetside 4spd 235 w/O.D. posi 3:90
In the Stovebolt Gallery
1990 Subaru Legacy Wagon AWD 2.2 5sp
2013 Ram Tradesman C/V
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