found the bottom shaft has the  stuck/locked  gear- really  wanted it to be the top shaft...  

So,   the axles  are now removed,  and  trans is sitting on a pallet on the floor.

Snag the  differential out next--   and  should be ready to  get serious.  

Assuming the worse,  and  shaft has to be cut...  where to cut to prevent/ minimize  carnage to other good  reusable  parts?   

Looks like they used  2 possible  shafts,   and  some of the gears need to be specific to that shaft... so I better pay attention when  gathering parts to put back exactly what was taken out.   

Do I dare  put a different  pinion shaft in there with out  keeping it's  ring gear mate-  they are, after all,  manufactured  as a  'set'...   

I've done a few  ring and pinions over the years,  but always was a matched set- regardless if they were  new or used.