Your situation is very similar to mine, I ordered the F250 V10 torqshift. The only rear end options you have is 4.10, 4.10LS, or 4.30LS. The 3.73 and 4.88 are only available on the diesel. I don't know what the diffrences are between the diesel anf gas torqshift, it probably has to do with shift points etc, due to different powercurve.