Got the bestop instatrunk installed over the 4th and it is great. Have seen a few unanswered questions about it and thought I would post it up and give feedback...answer questions.
Not sure why they list it as a 4 piece. It is actually 2 solid steel plates, a gasket and 2 bolts.
Was a little skeptical when assembling but once it is in, it is solid. Got before and after pics below. Still allows access to the rear storage, which I was concerned about.
This in in a 4 door, and I would say it leaves a good amount of space for other items between the seat and it. Didn't measure but looks like 20" or so.