That is a pretty good looking little Case. Being the 25th anniversary and having the full fenders she should also have the built in holding valve TVC. Nice score.
OK, I get the idea of a holding valve, but what is the TVC (or TCV as in your second post)?
I downloaded the manual and I see that there was a 3 point hitch assembly as well as a sleeve hitch assembly sold for use with the 220. It's also been my experience that 10 HP is plenty on most tractors to perform a wide variety of functions (plowing, tilling, snow removal). I understand that a hydraulic system is not efficient, but why would they have offered options that wouldn't perform well? It would only reflect poorly on the company.