Brian, if the 300 Cummins is the ISB engine I think you will be under powered and not able to easily increase HP & torque. Does it have a 5 speed trans?
The word elite is a sales gimmick most of the time. It may have a feature or two that is standard for this model that make it so.
I would recommend you have a qualified tech to go over the rig if you are considering a purchase before you buy.
Good luck and let us know the outcome.
Mike, RVIA & RVSA Certified Master RV Technician
Amy, Dr. Assistant - Roxie & Mei Ling, four legs each
2000 Gulf Stream Scenic Cruiser 450 hp & 1330# torque
06 Saturn Vue, 06 Chevy Z71 4x4 & 2014 Corvette Z51 M7