Thank you all for your help!

Hmmmm...I'm not sure about the terms "single gear" or "double gear" in regard to the PTO's...how would I know? Single speed or two speed PTO's? Or would it have to do with how many drive gears are involved between the tranny and the PTO shaft?

I'll have to take a look for model numbers on the PTO housings...I cleaned a couple inches of caked oily dirt off of them a couple months ago when I disconnected the cables prior to pulling the tranny to replace the cluth...but didn't notice any casting numbers at that time...but I wasn't looking for them either.

We do have a lot of truck equipment shops around here due to the oil and natural gas field industry that is the main biz around here. I didn't know if old 1959 type PTO's would be obsolete or not.

If nothing else, it would be no problem to take a couple digital photos. Either way, it makes me feel better to know that it won't be a big problem to fix them. Once I get the truck fixed up the way I want, it's going to spend a lot of time sitting at my backcountry place from early spring to late fall, being used intermittently for water and firewood hauling and such..I would hate to have to top off the tranny every time I drive it!