46 thus when bolt 46 and the matching bolt on the opposite outrigger are turned to move out of their respective fittings 48 they press tightly against the sides of the dump body and lock the entire unloader in place against sidewise or vertical movement fig3 is a detailed view of the rear clamp assembly of unloader 10 as seen from inside truck dump body 12 unloader 10 is seen clamped within coal chute opening 50 in tailgate 16 and resting on flat floor 26 screw auger conveyor 18 located within base channel 20 extends into the truck body and is rigidly attached to rear plate 28 when unloader 10 is constructed drive motor 24 is mounted on the far side of rear plate 28 and projects behind tailgate 16 unloader 10 is held within opening 50 by a simple 34 sandwich 34 clamp formed with angle irons 32 and 52 on the inside of tailgate 16 and rear plate 28 on the outside of tailgate 16 angle iron 32 rests on floor 26 passes under terminating cone 34 of unloader 10 and is held tightly against the inside surface of tailgate 16 by bolts 30 bolts 30 which also hold top angle iron 52 in place and against tailgate 16 pass through rear plate 28 and screw into threaded holes in angle irons 32 and 52 together angle irons 32 and 52 and rear plate 28.