I have a 69 grande w/302, im looking at getting some new wheels and selling off the wheels i have, ild like to get something in a 15x8 for the rears and 15x6 or 7 for the fronts, i checked the wheel sizeing chart thats on here, (dodgestang) and i think that will work, ive been looking, but im not sure how much back spacing i need to have or what wheels to go with, anyone have any suggestions? thanks