I see what you are saying about the 4th gen 2nd row seat angle affecting the JC Whitney seat. The links to the Jeep seat and seat belts are helpful. They make that seat in a black and grey as well as tan. Hopefully they have grey in stock.

I took out the carpeting and have it down to bare floor. Note, for those of us with cargo shelves there are 2 indented plastic pieces made into the floor carpeting (visible in bottom right photo). You take them out using a small allen wrench or something angled and rigid to fit in the holes and delicately swing out the tabs. You do not use a screwdriver and pry them out or they will break in half (I found this out the hard way).

Lastly, looks like your homemade plates are made from door hinges - is that correct?