Thanks for the help. I bought an Engel 15 Qt Portable Fridge/Freezer ENG MD14F today, $480 inc shipping and the TSL mounting plate. I preferred the new ARB but it was almost double the price.

It should fit and strapdown on the Bestop cargo rack I have mounted between the rear seats and rear window. With the frdge pushed to one side, I should still have some rearview sight.

Thought I'd share a picture of Engel, loaded for camping trip. The $33 Engel Transit Slide is worth getting, it locks the fridge onto my cargo tray, and very quick to remove.