Well, let's see. The brakelines run from the master cylinder, which is mounted on the body, to the proportioning valve, which is mounted on the frame. When the body and frame move farther apart, those lines will have to be longer. Typically, they have two or three loops for stress and vibration isolation, so you might be able to stretch them. I don't know if that is safe or not.

If you don't have hydraulic clutch linkage, you have a bellcrank mounted between the frame rail and the bellhousing. It will be OK, but the pushrod from the pedal to the bellcrank will need to be lengthened.

The driveshafts won't be affected as both the transfer case and axels are mounted to the frame. They don't move even if you take the body off.

If you have a shroud around the radiator, when the body moves up, the fan is likely to hit the bottom of the shroud. Dropping the radiator and its shroud by the amount of the lift will probably be a good idea. I don't think that should be difficult - just drill a new set of holes in the body where the radiator bolts up.

You might also have to get longer hoses from the gas cap to the tank.

If you only lift the body an inch, I think everything else will reach.