Not bad on the numbers, but he would have to derate the truck. The 1/2 ton and 3/4 ton gears don't interchange to my knowledge, so he would have to swap the entire axle. I think a transmission swap would do a little better in the 3/4 ton truck. A 27% overdrive will make an effective drive ratio of 3.00. That isn't to shabby! Use a transmission like the NV4500 and you wn't lose too much in the low range either.
