So my 78 ford f150 project I have decided to go for the look of having wider tires on back than in the front looking at Mickey Thompson street strip drag tires that are 29Hx12W and on the front 26Hx9W and 15 inch rims does any body know what my negative off set on my rims would need to be so they dont rub or when I hit a bump tear the tire or truck up??????