Help. i've got the collar off and the 4 bolts holding the bell housing to the transmission but i can't get the stupid bell to slip back to expose the u-joint. what am i doing wrong?

p.s. I have a pic but don't know how to post it.
thanks


Overland Blue, 1953 GMC 1/2T, 100-22, 228/1bbl, 4sp/4.10 6v, shortbed/fender side/5-window.