I can't say that I'm all that fond of mounting to that much cantilevered weight to sheet metal. It would be better to find one that uses a bumper as it's base.
I agree. And with those kinds of physics, you have to choose the lesser of two evils. Either have the gas can a little higher, concerning the COG, or stick the spare tire out farther from the body, concerning stress to the body and suspension. It's a matter of what you feel is more important, and you aren't wrong either way. I use a Garvin Wilderness bumper/carrier system, which holds the can a little higher than preferred, but oh-well.
Wish I had more to suggest and info to provide, but I've had a few and should probably zip-it before I get myself in to trouble on here.
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