I'm not a fan of the outside storage. If you attach it when you're heading out offroad, that's one thing, but I think the permanent storage is a bad idea. I'd be worried about it being a target for thieves, and getting rusted up if you live in a rainy climate. They're hard enough to use as it is without being all rusty, haha.
I don't know about the different gens of the T4R, but when I used to carry my 48" HiLift in my Jeep ZJ, it would fit right under my rear seat, along with a snatch strap, receiver shackle, and a pair of gloves. Flip the seat bottoms up, and there it was, ready to go.