Lift Kit experts needed

[Coley]

...Ok, I've got a buddy who is trying to sort out the results of 2"-3" lift on his 70' GMC 3/4 ton, 2wd.
I'm not an expert on this lifting stuff at all....but I had always assumed most 'lifting' was done down in the suspension where you lifted the frame/body off the lower driveline.
However, his kit has lifted the body off the frame 2"+ all around and what this has done on the front is create a big 2" gap between his bumper and his grill.
I found this to pretty odd given that lifting the body off the frame with spacers would mess with everything from steering angle, connection points, etc, etc.
Anyone know much about this?
He is trying to restore his bumper back to its original geometry relative to the grill.
Many Thanks!
Coley