I think ur driveshaft angle will be allright i have a friend with a 7 inch skyjacker suspension lift and 2 inch shackles and 3 inch body and he is running a 350 with a turbo 350 a downey adapter too duel toyota transfer cases and his front driveshaft angle is not that bad his back driveshaft is not very good but the front is ok havent got the truck out and drove it yet still work in progress but should be running by the end of the weekend.
But truck had same set up with 4 banger and 5speed and stock transfercase and driveshaft angle was fine so i wouldent worry about what they said about ur 5 inch lift.
just my .02 cents
good luck with the build
adam
