KDS

I would double check the caster angle. Too much negative can cause this.

How does it steer? Does the wheel seem "heavy". Does it return to center after a turn without too much effort? 

Well, If they're doing dumb rookie stuff, I hope they didn't mistake the Secondary radiator for the CAC.

That would explain a lot the coolant they found. lol

Early style EGR valve leaking back down the CAC cold tube?

I would check it carefully for metal. It may need injectors too!

Your supply side pressure sounds right, How about the volume? Is it running out of fuel just as it starts?

Keith, Yes, Pull the front end apart. It's not really that much work. Makes the engine in/out WAY easier. I left the trans in the truck on the last one.

I'll assume you have the correct rear lifting bracket. FYI, Reman engine may NOT have a fuel pump drive gear installed. Front cover will be fully installed, no gear ?????

Also, There may be 1 threaded bushing in the block for the ECM mounting, I've never been able to remove them. I'll get you a Cummins # if needed.

Snap-on now has some Voss Fitting fuel line removal sets, Some of those are a PITA in chassis. The tools help.