Repower Prop question

[thebottomfish]

So I found that the PO must have painted my original prop pretty heavy and it covered all the stamped numbers, I found where they were to figure out the prop and it is an OMC 763471. 15*15 aluminum propeller.
So I bought a replacement Solas 4 blade(new) and a stainless 3 blade solas(used)
Neither of them fit. It seems as if my original prop has a significantly longer hub. The splines on the 2 new props engage but they are about 2 inches from contacting the thrust washer (at the bullet) before the splines bottom out.
I'm imagining this is incorrect but no matter how much research I do, I don't find anything that a long hub prop exists for this motor and I can't imagine I need a thrust washer that's almost 3" thick.
Any ideas? I'm really at a loss here