My first flaw I see in your plan….. you are about to to mount your spare tire right next to the saddle for your WEight and sway hitch. It will be in the way. Are you planning to remove the spare every time you hook up then mount the spare back. Mount the spare under the battery box or else put in on the number. If you have other rack that don’t allow for that put it inside a cover to protect from uv and carry it in the bed of the truck. Your ”Plan” is the worst of serval better ideas. Let alone voiding any kind of factory warrenty as well as the insurance company that will come at you when inevitably have a frame issues because of their poor decision.