How to destroy an ORC

So I check over the mower and it seems ok. Start the tractor. Engage the pto and bring the mower up to full rpms before I put the tractor in gear. Tractor won't go in gear. It just grinds. Shut off the pto and the tractor goes in gear with no problem. Try again with the pto engaged. Won't go in gear. Take the tractor back to the shop and start really checking things. As far as I can tell, when I hit the rock it jammed the ORC tight so that it acts like it's just an extension of the pto shaft. Destroyed a $60 ORC to save a $2 shear bolt.

Is there a special ORC for the NAA? Went to Farm & Fleet and bought another and I can't get the holes in the ORC and the pto shaft to line up. F&F didn't have a 1 1/8 so I bought a 1 3/8 with an adapter. I can't get it slide far enough on the shaft to line the holes, there's a flange around the shaft that the body of the ORC hits. Or, do I have to buy a 1 1/8 because a 1 3/8 is larger?

I just replaced my chewed up ORC on my 53 NAA a few months ago. It is a 1 1/8 6 point female to 1 3/8 six point male. The only dealer left in Southern Maryland is JD, but they got it for me for about $60. It is an aftermarked brand, HubCity. I assume your hog wants a 1 3/8 six point. See if you can get your money back on the adapter and go for a single unit ORC. The pin should be very easy to drive in.

Tom