driveshaft yoke problem
 

i just had my getrag360 out for service in my 89 d350 and now upon reassembly the rear yoke on the tranny seems to go in past the end of the splines which isnt letting the nut tighten down on it.[verymad] i have another output shaft just laying around and it does the same. it has been a while since i took it apart so im thinking im missing something but i dont know what? any ideas?