Where to fing gears for 741 case?

oldkimmer said
Yes gears interchange between 741 and 742 cases even though the 741 has 1 3/8 pinion and the 742 has 1 3/4 the collar in the 741 is 1 3/4 outside dia.....kim.........
Thats exactly what I have had done. I didn't know that. (Or any better when I had it done.)
Still working today.