Ford racing billet steel flywheel ID help

Hey everyone, i got a newish billet steel flywheel for like 70 bucks. I bought it from a good friend who got it from a friend. I wanted to verify the 50oz imbalance, as its going on my new 310. The whole problem is that there is no part numbers anywhere on this thing. I looked at pictures of them from parts sites, and it looks like the 28 has a weight on it, as does the 50, but a couple 50s i saw have the same holes drilled in the same locations as mine. I know every individual peice is different, but its really all i got.

My question is there any way to propery ID this thing without having to bring it to the machinist?
here is a few pics

sorry my cats love mustang parts.