Anybody know the correct back spacing for these trucks? I am planning to put a 15X8 steel wheels with 245/60-15 tires front and rear. Specifically the Series 84 black Daytona wheel from US wheels. http://www.uswheel.com/wheel.cfm?category=59

The 5.5 wheel have a -13mm offset. which is a .51 inch offset... doesn't seem right. I'll be painting them the same color as the truck, Petty Blue. I want it to have sort of a nascar-truck look. Lowered and on these wheels and tires.