383 Harmonic balancer question

I Believe someone has drill a bunch of holes to balance an
Aftermarket Rotating Assembly. If you have a stock factory weight
assembly it would be throw the engine way out of balance. I have been
around these cars since new and I have not seen a balancer drilled like that
one out of the factory.

I have a Brand New in Box Cat neutral balance High Performance Balancer
that is more reliable and safer at high RPM for a Big Block. I think it cost me
around $300. years ago. I would sell it for $85.00 plus the ride if anyone needs it