this truck will be my pulling rig but it will also get driven empty a lot will probably do lots of driving at 70 to 80 MPH i just thought the 401 and Allison would be kind of neat i already have the 454 in the truck but no exhaust manifolds or radiator(i don't have them)i also have a dana 70HD with 8 lug hubs out of a Chevy 1 ton so i was also going to get a 4X4 front axle with the 8 lug hubs so i could use the truck in the winter too. also how much stronger is the Allison compared to the th 400?