well, the Bush Hog web site said
Recomm. Tractor HP 60" 25 to 40
72" 30 to 45
the TC33 is 33 gross HP and 27 PTO hp...
so I'd say a 72 was marginal at best?
My ground is flat, mostly pasture, and never very tall...Seems like a 6' finish mower wouldn't be as taxing on the TC33.