KEITH - the plastic hydro fans were really fragile, lots of them don't even survive installation! They're kinda like the fiber PTO thrust buttons, you should buy them 2-3 at a time.
I went to a household auction in East Moline, IL back around 1980, before I bought my CC #72 in Jan of '81. There was a #147 and another gear drive CC, like a 102 or 104. There was a cardboard box of spare parts/belts/blades that sold as part of the 147 and it had two broken elec. lift units in it that had been taken off & replaced in the roughly ten yrs the tractor had been run.
The steering gear boxes are another part that really wasn't up to the durability level of the rest of the CC tractors. At least you can still get parts for them relatively cheap. I bought a whole new gearbox for my 72 about 8-10 yrs ago and installed it five years ago. Even on the spring tune-up sale from my local Case/IH & CC dealer it was almost $300 with tax back then. But you can't really use the tractor if you can't steer it. My old gear box was really worn everywhere. I'd rebuilt it at least twice. The top thrust bearing & stamped race had pushed up thru the top of the diecast housing and the steering tube was loose in the casting. I had to install a heavy wall steel sleeve made from 1-1/2" OD x 3/4" ID tubing to tie everything together.