327 chevy truck crank shaft

[68chevylwb]

i have a 68 chevy truck with a 327. the crankshaft is not dilled where the balancer mounts on the crank.my 350 chevy v8 motor has a bolt that holds the balancer on. i talked to the engine builder and he said the crankshafts on 327 engines are not drilled. that started with chevy 350 v8 motors.
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would anyone know if this is right????
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