No, the 3100 beds just have 2 stake pockets on a side.
It kind of makes sense that the longer 3/4 ton beds would have some extra bed wood support between the #3 cross sill that sits on the frame and the #2 that floats above the frame (at least it does on my truck.)
If you could post a picture of how that cross-sill bolts on to the bedside, that would help chuck2213 figure out how to deal with that.
