I came upon a video on YouTube today that brought to mind some questions. It’s an old video titled “Bob Stewart’s Display.mov” and he has a very impressive collection of high crop 15s and twenty twos. Would the castings be the same between all high crop models? If so, could I take a set of drop downs and have a mold made out of them? What kind of business would make re-castings, and would something like that cost an arm and a leg?      

I believe that was at Portland Indiana in 2010 maybe, I had my 75 at the show.

  That would be quite the endeavor.  Many more of the parts on the high crop are different not just the drop. Like sprockets, Springs, sprocket covers, hitch assemblies……

Hm. I wonder if the rear sprockets were a one off for the machine or if they were robbed from another model. I believe the pitch from a 22 is the same as a d2, so I wonder if a d4 sprocket would have the same pitch, just bigger diameter. All good information to sort out. It looks to me like the 22 version was on the same undercarriage as the 10. Or are my eyes playing tricks? Luckily we have a good HC to compare to.

The Twenty-Two HC tractor used the HC TEN finals and tracks etc. Never paid any attention on how the larger steering clutches and castings were adapted to the TEN drop down gearing.
The engine was sleeved down to a smaller bore so the finals wouldn't be torn up with higher power Twenty-Two engine.