17x8 and 17x10.5 cobra R wheels..

[Junglejoe]

I am going to purchase these wheels which will help me to get busy on the v8 engine swap. Can anyone that knows tell me what the backspacing needs to be before I order them? I "THINK" they are like 6.81 inch on the rear backspacing on the wheels. Stock width ranger reared is what I will be running with a 315/35/17 on the rear tires.. Am pretty sure those will tuck with out any rubbing issues?? OR I am going to have a custom set of wheels made to order that are 17x11 rears with 8's up front with whatever back spacing I need