Sable surker: I thought I had adequately explained the gasket deal but appearantly not. Just measure the thickness of the two you took off and replace accordingly. If you no longer have them just start with a .020, snug it and see if you can feel any play on the output shaft with the gear engaged. If not then remove and add an .010 gasket and do it again. It's not the huge deal you think it is. Don't be intimidated by these guys hollering backlash, I think your making to much of it. If it will shift into and out of gear with out grinding, or clattering when it's running, then you are good to go. It should shift easily by hand on the shift lever. If it does then also make sure you have a functional cable as they get pretty crummy and hosed up with rust, dirt, etc. Then it's off to the races for you.
FWIW Dep't. Muncie was only an assembly and marketing company for Chelsea PTO's for the first 35+ years of their existance. Finally they developed their own line and manufacture them today. They are now blue instead of red and nearly all have aluminum case. They are now owned by an Italian company. Chelsea PTO's are now part of the Parker Hydraulics group and the Spicer brand is kapoot I think. Dana Corp went bankrupt and disposed of a lot of brands over the years, Chelsea being one of them. The two models you referred to are both Chelsea made models. There were about 5 or 6 of the basic single gear Chelsea PTO's. It's a lot more fun when you start talking about the hundreds of possible models/configurations on the double gear units.
