I had to space my wheels out to make them fit. I briefly had them on an old car and actually posted pic here on Stangnet a couple of years ago. I'll try to find them.
I did a lot a searching to see if the 03 Cobra style replica would fit with Fox spindles and 5 lug rotor upgrade like in the the upgrade kits or with the Lincoln mark VIII rotors. Everything I read said they would not mount up and the dust cap would interfere with the wheels center cap and they were right. But I was determined to make it work and with a little patients and you can do it with simple tools like a die grinder with a carbide cutting burr, grinder and hammer.
Here is how I did it and the first picture shows my 03 Cobra replica from American Muscle 17x9 mount flush to the rotor and center cap installed.
The spindel end is formed right to the cap. I hammered it while on to make that clearance.
You can see here with the wheel off how I shaped the end of the spindle hat
and hammered down and shaped the dust cap as well.
With the dust cap off you can see how I ground down the spindle end where it had no thread right to the cotter pin hole. I also rounded the edges and then sanded with die grinder.
Here for reference is the other spindle in stock form so you can see I took it down about a 1/8 inch.
Sorry not the greatest picture here but the reason the wheel does not fit is the rotor is that the inside of the wheel center is rounded at the back side where the cap fingers are. And of course the rotor hat is 90 degree angle
Here is another crappy picture but you can see how I cut down the bottom of the cap on my grinder and then hammered the round end down. I then used a piece of wood and a socket extension to pop back out the center where the spindle needed room.
From the center of the rotor hat its reduced about 1/16, but it is round down on the edges to about 1/4 inch. This is what need to fit the round interface of the wheel center.
You can see here the rotor before with the sharp 90 degree edges.
It doesn't show it here but this rotor is about 1/16 inch shorter now. You can see I screwed up holding the flat edge flat on the rotor top.
The center caps also had some work done to them. You can see the inner spring was removed to it would fit over the dust cap. Also the ends of the fingers, the little clips were ground down.