look at the bottom molding of the step, should line up pretty well with the rocker molding below the door .... you need to look at the
stance of the whole truck, the beds do really slope to the front if the suspension is in good shape .... check that measurement cab-to-box at both top and bottom, if what you're saying is the bed is closer at the top, then yes you might need a bit thicker anti-squeak under the front
Bill
