From what I can see it looks like you're showing your front drive line coming off the front of your T-case and heading to your front axle
There is another style of PTO that is integrated into the transfer case that supplies power to the to the rear of the truck where the water pump sits on a water truck
This is how my old M50 water truck works and it doesn't look like a normal PTO where something is bolted to the side, it's integrated into the case and has an oil line that feeds from the bottom of the transfer case with a pump up to the top to lubricate it .
You would see a little shaft sticking out where a baby drive line goes, a long one, and its up high on the case towards the drivers side, on the rear of the case obviously .
These style cases were used on water trucks and fuel trucks i.e. M50 M49, I think there is also anorher designation or two for some reason, they are a neat case IMO and they give you options