New steering coupler doesn't fit!

So here's my situation. I just repainted my steering column and figured I'd rebuild and replace the coupler before reconnecting the steering. I ordered what I thought was an actual OEM replacement coupler because after looking on eBay it looks like many of the reproductions are of lesser quality. So I ordered one from Richard Ehrenberg and it looks just like my original except one major problem. I can't get it to slide onto the shaft that comes off of the steering box. The old one is all dented and hammered on but slides on and off but is snug. The new one looks right but after pushing and hammering on the steering column I can only get the coupler on not even half way. I marked on the shaft and the old coupler to properly align the old and new coupler but can't figure out how to get the new one on. Is it common for couplers to be a bear to get to fit? Are there variances in tolerances so one is snug and others too tight? Any suggestions would be appreciated.

Carl