There is a drawing of the clutch with dimensions in the operators manual. I don't have one here at the house so if you don't have yours, I'll have to try to get to it on Monday, Mondays are crazy as this is the busy season but I will try to get to it. Dwayne is correct, there is (I think it is .030 inch) gap between the three PTO fingers and the 3 main fingers and a gap that equates to about 1" of pedal free travel required to move the throw out bearing from rest to engage the first set of fingers. If you just tried to rough up your disk and reinstall, that will likely be your problem. Slipping of the clutch gernerates tremendous heat and glazes the friction material, and the pressure plate and I suspect it damages the bellville spring, less spring pressure means slipping clutch and the ontly thing that can keep the tractor from moving if all the gears are engaged is the clutch slipping.
I would suggest you put in a comlete clutch package, but certainly at least the main disk. We do have complete cluch packs in stock.
I know this is proably bad news, its a fair bit of work to split the tractor, BUT the good news is it is much faster the second time!