[Pyrotechnic]

There should be enough frame back there do whatever you want, but you will most likely have to do something with the front spring hangers as they will have to be moved forward on the frame, and the frame goes lower as it goes under the cab. You will most likely have to get rid of the saddle gas tanks as well. As the front of the leaf springs will occupy their space.

I take it you want to remove 1 foot from the front of a 6.5 foot short bed ?