This isn't a full write-up, as it's already been done, just a brief summary.
One of the reasons I narrowed the rear bumper was that when dropping off ledges and stuff there was enough body flex for the bumper to push up against the rear quarter panel. This resulted in some minor damage to the rear panels. So I added some River Raider corners.
Installation is pretty straight forward, but took a little longer than I anticipated, about six hours altogether.
First thing I did was paint them, through some Rustoleum Hammered paint on the inside, as I happened to have plenty, and used Rustoleum Bed Liner spray on the outside.
Once that was dry, I mounted some ORO LiteDots in the corners and connected the connectors off the factory lights. You need to pay attention to where the wires come through the mounting hole in corners as the LiteDot wiring is not always dead center.
I used Warrior Products 50 watt resistors across the brake/turn signal wiring, so that the turn signals would flash correctly. These come with a nice heat sink and can be bolted inside the rear quarter panel.
Taping off the whole corner is a good idea while you test fit the corners to avoid scratching the paint. Use the provided templates and cut out the quarter panel.
Offer up the corners and plug in your light connector and check the lights work correctly.
An extra pair of hands is useful for the next part, but not essential. Test fit the corners and mark the mounting holes. If you follow the edge of the tailgate opening there isn't too many ways they will fit. Mark the holes and drill a 1/8" pilot hole, followed by a 5/8" step drill.
Paint all bare metal with some paint before final mounting of the corners. make sure none of the wiring is near the resistors.
Drop the rubber inserts into the holes, offer up the corners and get each bolt started. I found it best to tighten each one a little at a time, doing 3 or 4 complete passes.
The factory fuel cap surround needs a little trimming to fit, but is very easy to do. The black plastic trim pieces over the hinge no longer fit. The body side ones may fit with some trimming, but I just painted the hinge black and used the tailgate side covers which still fit fine.
Finally, seal around the corners with some silicone.
They follow the lines around the corner pretty well, but due to the curve of the panel, not so well at the bottom side corner. However some silicone soon filled that gap and as it is underneath you can't see it anyway.
These things are solid once installed, they are 3/16" steel, well made and will definitely take a beating.
The LiteDots work great, they include tail, brake/turn, back-up lights and also have three LED's on the side. They are really bright to look at, but don't give off much usable light when in reverse. I also through some Recon LED marker lights in the front so they'd match better.