I have a 1 ton with a dump bed. My pto comes off the SM 420 transmission. I don't know how common these pto's are so you might have a problem locating one, if that is the route you are going. I also don't know what transmission you have, but they used the SM 420's on lots of these trucks.
I've got a lever in the cab that connects to the valve that is back by the hydraulic tank and cylinders.
I've not had the chance to use mine to see if it works or not, but I've not heard anything bad about them. It's got a marking on it, but it's still too gunked up with grease for me to read well... and I've already scraped about 100 lb's of grease and grime off this truck.
