Some 03-04 came with a thick IRS bolt. If yours did you will have to do what DSG said.. Or you can do what I did and these are the only ones, I would go with. They are from Lightning Force Performance and cost around 100.00 tell them your with Wicked Stangs and should get a discount.
LFP 3/8'' Hubcentric Wheel Spacer Kit
LFP 3/8'' Hubcentric Wheel Spacer Kit
Wheel Spacers are designed to help give you a more aggressive wider stance. In addition to that this kit will help those who runnning an IRS more clearance when running a wider tire or larger wheel such as the custom Mag's.
LFP offers the only true Hubcentric Wheel Spacers on the Market. Do not be fooled by cheap imitaions. Hubcentric Wheel Spacers allow you to mount flush on your rotors. Other spacers you have to shim to eliminate the space between the spacer and the rotor and can cause vibration. Hubcentric spacers are perfectly balanced with 0 vibration.
LFP complete Hubcentric Wheel Spacer kit. CNC Machined from Billet Aluminum the 3/8" Wheel Spacer and Extended Lug Nut Kit was designed to help those running wider tires and wheels on a 1999+ IRS equipped Mustang. Wheel Spacers allow clearance for use of custom mag or steel wheels on Cobra & Mach I.LFP 3/8'' Hubcentric Wheel Spacer Kit
Wheel Spacers are designed to help give you a more aggressive wider stance. In addition to that this kit will help those who runnning an IRS more clearance when running a wider tire or larger wheel such as the custom Mag's.
LFP offers the only true Hubcentric Wheel Spacers on the Market. Do not be fooled by cheap imitaions. Hubcentric Wheel Spacers allow you to mount flush on your rotors. Other spacers you have to shim to eliminate the space between the spacer and the rotor and can cause vibration. Hubcentric spacers are perfectly balanced with 0 vibration.
LFP complete Hubcentric Wheel Spacer kit. CNC Machined from Billet Aluminum the 3/8" Wheel Spacer and Extended Lug Nut Kit was designed to help those running wider tires and wheels on a 1999+ IRS equipped Mustang. Wheel Spacers allow clearance for use of custom mag or steel wheels on Cobra & Mach I.