I've done it with a 2nd gen 55 on a 99 Ram 2500 frame. What you choose to put in front of the engine will dictate how you fit it. If you stay with a moderately-sized radiator and ditch (or relocate) the intercooler then you can fit it without setting it back too far under the dash. Mine has an oversized radiator, AC condenser, and pretty big intercooler so I have mine set back 14 inches so it comes all the way back to the base of the dash and really crowds your feet. With that, I had to offset the brake and gas pedal. Mine is not yet on the road, so I'm not sure how much of an irritation that will be. I do my share of driving on out vanpool at work and it is pretty much the same way and it doesn't feel awkward at all so maybe it will be fine (I also have cruise control I the 55). Link in my signature below.
