does anyone know if I have to have a special tool to turn the engine over or is there another way to do it.
There is an engine turning tool, although if you can get something on the crank pulley bolt that should do the trick. Shouldn't take much effort to turn if you can get a half in ratchet on it. May need a second hand to push a "timing pin" in the flywheel slot. Just turn it till timing pin slide in and figure if number one or number four is loose and have at it.
You definitely don't "have to have" the tool to set the valves. If you can get a hold of the belt and the fan, you should be able to turn it that way slowly.
Iirc correctly the crank drives the hyd pump. You could probably use a nylon strap filter wrench on the crank pulley and turn it over that way.. All those cummins engine baring tools are the same I bet there's ones for sale in your area cheap enough to make life easier.
the valves are done.I took an old deep socket that fit in the hole,ground some teeth on it with a die grinder and turned it over with a 1/2 inch drive rachet.worked like a charm