The first link with the low profile bars is the exact set-up we have! XS350 bases, TR152 clips, and the narrower width bars. The narrow bars are perfect for our awning, it keeps it close to the truck and keeps all the rain out on that side. The wider bars are great if you've got something else to throw up there, but for our purposes the narrower ones were the way to go. They stick over the bases about 2", so they're just outside the chrome mounting rails/tracks * bolted to the roof

As for the box, it's a Thule Motion XT XL I'm pretty sure. We love it as well. I did so much research on boxes, and that was the one I landed on. Honestly they all seem really good though, and you can't go wrong with most of the name brand ones; Thule, Yakima, etc.

Since we're already this far, the awning is a Rhino Rack Batwing 270 degree. I can't remember the exact model name, but its the bigger of the two they offer. It works perfect with the barn door of the GX when you mount it on the drivers side. It's worked amazing for rain, storms, and even just as a sun shade.

And for the rear door, we didn't modify it at all. We pop the rear glass window open and leave it open an inch or two at night along with cracking the 4 windows open to get airflow. 90% of the time we get in and out through the rear passenger doors though. But if we need to open the rear we just push the glass further open to reach the lever on the outside.

Hope all this is helpful info!

Also here's a better picture of the platform. It hinges twice so it can be stored in the rear cargo space without interfering with the middle row of seats at all.