Care to explain? The factory TTB crossmember tucked into the "C" of the frame rails, mine will be butted up against them. But that's really the only difference, unless I'm missing something, which is 100% possible. Roper designs did the swap the same way as me, but with a Shortened D50 beam setup, and is pulling 17.5" travel.So are you going to notch the frame to clear the diff? Otherwise you will loose a bunch of uptravel.