LA pulleys not lining up with Magnum Balancer

The balancer is off a 95 5.2L out of a RAM, the pulley is off a industrial LA318 from a 70s dump truck, no matter how I turn the pulley I can only get 5 out of the 6 bolt holes to line up. Is this common? I am thinking just slot the hole to make it large enough for the bolt to work.3BDD4E98-957D-4C82-ACD2-31E507ABC93A.jpeg