my tranny is open, i cannot get into reverse, even when i take the gears off and just stick the shift forks in i cannot get it into reverse. if i pull up on it, it will go into reverse.

i did a search it sounds like it's the shift fork...do i also need to replace the shaft holding the shift fork? could it be any of the shifting arms be messed up? i check the piece that connects to the shift linkage and it is not bent.