[low 84]

well if you are keeping your axle stock (i.e. not narrowing it) and you want the outside of the 325/50 to be approximatly in the same position of your current tire. then its pretty easy. say you have a 15X8 with 4.5 backspace and you want to go to a 15X12. just add the extra width of the wheel to the backspace, this effectively puts all of that wider rubber inward of where you current tires are now. the 12 ich wheel is 4 inches wider than the 8 so add 4 inches to the backspace. 8.5 backspace on the 12 inch wheel. this wheel would have to be custom made and you would have to look out to make sure its not gonna rub your frame or springs on the inside. i don't think i've ever seen a 15X12 on a non narrowed axle that sits inside the fender. thats alot of wheel. reason i am going with 15X10's with a 325/50 bfg drag radial