I need to check/replace the bull gear in between my T18 and D20, does anybody know if you can go through the tailshaft of the transfer case? It looks like you can take off the back cone where the rear output shaft is and access everything through there. Has anybody done it this way? I just put tranny and Tcase back in and still has a grinding noise so I suspect the bull gear is worn. I'm trying not to have to pull the Tcase again.