To my knowledge, these are the applicable TMs for our trucks. It took me years but I finally accumulated these.
The Operator's Manual. This should be in the glove box.
The "20" manual. This is the stuff that the Motor Pool could do.
And the parts book for the Motor Pool.
The next one is for like Depot Maintenance, the stuff we were not supposed to touch!
And the Depot parts manual. It has just about everything.
It took me years to acquire all of these books. But they are invaluable when you want to work on something (if you are a "stock" guy like me).