it's not a square step up, it's tapered like this:
Even so, I'd like to smooth it a bit more with a leading edge extending over the cab a little. I'm also concerned about the sides, which have a one inch gap from roofline all the way to the frame, plus additional rounding on the trailing edge of the cab and a sort of 'scoop' shape to the leading edge of the cap.
I was thinking of some clear plastic film to help protect the paint, if anyone knows any brands to search on...