im buying a m1008 6.2 with 4.56s gears, detroit rear welded front. ive got 60/14 that i rebuilt, 5.13s, disc rear, detroits in both. would you swap in the 5.13 axles? thats what im leaning towards since ive spent so much money on them and dont really wana part with them (they only have 1500 miles since i rebuilt them), but i wanna see what people say. keep in mind im going to be swapping in a tranny with overdrive. 5.13s, overdrive and 42's. what do you think?

highway rpms with 4.56 and overdrive will be at 1850, which is best mpg for the 6.2.