Traitor!!! Wimps turn to the dark side.....J/K...
The cummins bolts into the 99-03 easier than the OBS due to the engine compartment depth, front to back. Think about it, the OBS is tough putting in a 3" DP and the SD putting in a 4" DP is a piece of cake. With a cummins you need all the clearance you can get. That engine is long and your turbo and DP are on the passenger side right where the evap box is.
Just a thought, Bean has done a few using destroked parts, might be worth a call to him for pointers.