I am not sure but you should have 6 bolts and maybe 2 nuts who hold the winch on dozer
http://www.alliedsystems.com/pdf/Winch/Manuals/599181W.pdf
Give this a shot-I can't go through it now, but I recall from when I pulled mine that Hector is correct. Also, the weight of the winch makes it want to hang on to those large stud bolts. I am guessing you are lifting the back end a little while you are trying to wedge in your pry bar. I did not have any trouble with the coupling wanting to hang on to the transmission shaft. I was able to pull mine with a standard hand pump hydraulic cherry picker.
Good Luck
There should be four nuts at the bottom, two are underneath, quite close to the outer ones.
Besides the two blocks that bolt to the top rear of the tranny, there are six nuts on the rear plus two bolts underneath. Usually the splined coupling won't hang you up coming apart. I used a 5/8" eyebolt in the hole just above the drum. .it balances pretty good with that as a lift point.
Uses six studs, same as the drawbar brackets....plus the two top mount brackets.
Thanks guys.
I shall try again.