the difference is HUGE for potential buyer.

 

horsepower for starters lol.
I don't know about the internals bore, stroke, cam, valves, computer or the cp3 pump. But I can tell you the injectors, lift pump are different.

 

Mainly tuning and a big of cam profile. Nothing that can't be remedied with a Smarty!

The injectors are a slightly different design and are not interchangeable with the 04.5+ CR trucks.

Besides, event the 325 / 610 engines are torque limited to approx 565 ft/lbs.....so it's really a wash.