I am installing a 2001 humvee motor in a 1998 Chev K3500. Truck has a 3" body lift & 6" suspension lift. Will the motor fit or will I have to change the intake manifold and turbo? Will the intake manifold from my 6.5 bolt to the heads of the humvee?

You have several options:

Modify the fire wall for clearance.
Move the motor forward! this will require you to modify both your driveshafts.
Use your truck style intake and heads.

The look of the Hummer system is clean. I esspecially like the exhaust manifolds routing up to the center turbo.

The reason I personally would NOT use the Hummer system, is the fact that it would be nearly impossible to install an intercooler, which this motor is in desperate need of.

To switch to a truck intake you need to change the heads, turbo, upper and lower intake manifold, not cheap.

Cheapest alternative would be to modify the firewall (Your 3" body lift will be your good buddy for this option), but then your still stuck with the "lack of" intercooler dilema.

Hope this info helps.