The most "radical" things I've seen so far for the KK have been "Atthehelm" bumpers, off road lights, rock lights, LED driving lights, rock rails, and lifted 4 inches. So far the most modded KK has been a SFA swap done for a dealership by one of their guys. There's a link somewhere for that.
There isn't a magazine you can just open and point and have a custom KK. We've all only been able to do a few things here and there.
Good luck and post up any questions you might have.
Hypertech Max Energy
CAI, Gibson exhaust, 4.7L throttle body