What is it a stick? do you have like a half inch or so left to go in? If so, just push the clutch in and it should slide. Make sure the everything is lined up correctly as well.
Clutch alignment tool, the plastic ones are about $3 at most auto parts stores. It looks just like the input shaft of the transmission. You use it to line up the clutch disk with the pilot bearing hole. It makes the job simpler, as the clutch disk is almost perfectly aligned when you silde the transmission in place. As Timmy2734 said, you may have to push in on the clutch pedal to get it to go the last 1/2". I used some 7/16" threaded rod screwed into the mount holes to help align the trans.
No, Im having a problem with the fork falling off and I cant get it striaght so I can put it all the way thru. Im doing this job alone with 4 stands and 1 jack.