After much debate and realizing the only way to gain more cargo space in the JKUR was to add some sort of luggage rack. I decided to pursue an option that would allow me to use it throughout the year, for skiing, camping, extended vacation and keep the hitch open for our jetski.
I found a used Yakima Rocketbox on Craigslist that came with the towers and cross bars for a Jeep Grand Cherokee (WJ). The box is 7ft long and has more than enough room for a couple sets of skis, a snowboard and other luggage to keep the interior of the Jeep clutter free. Because this already had the WJ/XJ/ZJ towers I decided to pick up a used XJ rack after reading this article:
Jeep JK Rubicon Recycled Roof Rack: Off-Road.com
As you see in the article the opted to place the rails just outside the last rib support on the hard top. In the last photo you can see the crossbars are slightly stretched, I would not feel comfortable running the load on bars this way.
Here is what I did instead, I placed them on the last rib and used Yakima Crossbars with backing plates.
The crossbars on the XJ system could be cut, and I may do it in the future, but the Yakima mounts are just so much more solid.
On the Cherokee rails there are 5 holes, I opted not to drill the middle one as it goes through the main support on the roof
I made some backing plates for mine out of 1 1/4" x 1/4" steel, but should have used aluminum. I aligned the holes with the XJ rails then drilled and tapped them. They are coated in Flexidip rubberized paint to help make them feel more at home.
Here is the backing plates installed, I plan on cutting the bolts flush with the plate to hide them from the underside.
Here is the overall end result, you can see the XJ cross bar is sitting slightly over the rail, I won't be using those right now, however I do have to say the Cherokee cross bars make it almost factory looking.
There is a slight (1/16") gap at the end caps, some black RTV will help hide this. I did use RTV at each screw and rubber washers on the underside hopefully that will be enough to keep the water out. I am thinking with the backing plates I should be able to use this to lift the hard top off the Jeep as well. Once the hard top is back on the JK for the season, I will add a photo of the Jeep and one with the rocket box up there.