What Sam has worked up for this replacement shaft should make for a trouble-free design. Once all this rain stops, I plan to hook up some of my rear PTO implements to see how it handles the load. I don't expect any problems, I don't dare to try and drag the 48" tiller into the garden for a while lest the stack will be the only thing left showing. I think it's time to take out the bushhog.
The hardest part of the shaft install was getting the pump shaft drilled and tapped. I found that the shaft varied in hardness where the cobalt drill started out going right along into the shaft, then the next minute the progress virtually stopped. I had to dig out the carbide drill bits. After a short time, it started drilling easy again. I was lucky enough to order a pump adapter, bolt and belville washer from my cub dealer. I measured how far the bolt protruded through the pump adapter, subtracted the thickness of the belville washer to get the reach of the bolt when installed, then added to the depth of the drilled hole in the pump shaft by the amount of taper on the 1/4-20 tap to make sure the hole was threaded deep enough to accept the bolt. Although I could have tried to use a bottoming tap to skip the last step.