I installed the balancer with a comp cams balancer install tool. It was very tight to install. I suspected i should have maybe had it honed to make it easier to install...
Every aftermarket damper I've used has had to be honed. You need to mic the crank snout and measure the id of the damper to see how much press fit you have. If it needs to be honed have a machine shop hone it.
I don't remember the od of the crank but here is what ATI recommends.