so if I have it right you are running a 12.5 tire on a 6.75 wide wheel. going to a 8 inch wheel will help with your rubbing problem, you will still be pinching the tire and you can run tire screws if you like. the truck will be more stable with the tire and wheel more properly matched. I am running 12 inch wide 16.5 rims and have only lost a bead once. I usually run single digit pressure rock crawling. I was being winched sideways after a breakdown. I was not moving and he kept pulling in cable. POOF! Remember that PSI is Pounds Per Square Inch. You can get away with a lot lower pressures then most people think. 15's, 16's, 17's and so on can run 1-2 psi because of the safety bead.