Or you could go to thecustomwheelshop.com and get bullits there with the staggered fitment. 18x9's for the front and 18x10's for the rear. They'll be drilled with the proper backspacing and bolt pattern eliminating the need to do a hub swap... unless you're also gonna do the big brake packages for the mustangs.
My wheels are from the custom wheel shop and they fit perfectly. I have the '03 cobra replicas 17x9's all the way around
2001 Ford F-150 Supercrew
1995 Thunderbird LX