[evldave]

Rather than add the extra 30# of weight to the roof, why not just get a long threaded hook and large (4") wingnut. Hook to hook through the mesh of the gobi, string it through one of the holes in the wheel and thread on the wingnut. I guarantee it will hold as tight as the stock mount, and you don't need to use a strap to prevent vibration because you are using the tension of the hook to hold the tire against the rack itself. Cuts down on the weight on the rack to keep COG lower.

I've been using this setup on my rack for years and have never had a failure (same hook, same wingnut for 3x vehicles and 10+ years). I think it looks much cleaner - you only see the tire and don't really see the hook unless you are really looking. It's also very stable because the tire is fully pressed against the rack instead of floating above on the tire mount.

I like your idea of Jerry Can mount on the back. I had previously had my bike mount, but it still left the vent showing, I'll probably put together a 2x jerry can, hi-lift, shovel/axe, bike mount. Should be about the same as a tire/bike mount and look really cool too!