I think you should go for it. I've long thought about changing my KK to have black fender flares (and would probably do from the belt-line down).....I've just had a few other KK projects I've been working on for nearly 1.5 years.
Below is a photo of my 2 rear fender flare insides after shortening for my
KK Heavy Duty Basic Rear Bumper:

Along the top down to where the rear fender flare juts out to go around the OEM bumper side, there are 6 (I'll call them "standard") arrow-head style fender clips (as shown on the right in the below photo) that push into a round hole. My OEM ones were gray. Then there are 3 more complex fender clips (as shown on the left in the below photo) that push into an oblong hole on the OEM rear bumper sides. My OEM ones were black and are much more expensive than the "standard" arrow-head style which also are used to hold on the front fender flares.

It is pretty easy to disengage the (6) gray arrow-head style clips along the top part of the rear fender flares. The (3) lower black, more complex, clips are harder to disengage and if you pull too hard, they'll just break in two (also had this happen when wheeling and a midwestern tree root wrapped around my rear tire and then released energy causing my rear fender flare to go flying across the woods.

kskj ought to recall that as he was standing right there). Use a plastic flat bladed tool to carefully pinch in one side of the arrow head of the (6), starting at the passenger door side and work your way down to the (3) lower and harder to remove black clips. It might be a lot easier to use a small flat bladed screw driver to try to get the small tabs on each side of these clips pushed into the inside of the rear flare to get them to release from the flare and then after the flare is removed, then you could remove these (3) p.i.t.a. clips from the KK's rear bumper.
Here's what I've got for P/Ns from the last time I bought some:
1. "Standard" arrow-head style fender clips, the gray ones in the above photo (for top 6 on rear and for all of front fender flares) = Jeep P/N 55157055AA (cost me $1.45 per clip at my dealer)
2. More complex fender clips, the black ones in the above photo (for the lower 3 on the rear fender flare) = Jeep P/N 5189180AA (cost me $7.50 per clip at my dealer, list is $10.00 each
)
Hope this helps. Keep us posted.

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2009 KK Limited 4x4Jeep Green/partially dechromed/Sunroof/OEM Skids/
Gray Leather/uConnect GPS-Nav/DVD Head Rests/
MtnLuvr's Off-Road Front Winch Bumper, Heavy Duty Rock Sliders, Heavy Duty Off-Road Rear Bumper/JBA 4" AaS Lift w/UCAs/16x8's w/ 245/75R16 GY MT/Rs
Coming:
