Don't know on that. Usually the beds will be the same length but cab styles differ. . I have seen a lot of comical mis-fit caps on beds. . best thing to do would be to test fit it and see how it matches up. .
if it fits the bed good but not square with the cab then thats OK. . Remember the old sheet metal caps of old ? . . not very form fitting to truck cabs. If it fits good, I'd do it.