A 99-04 would be a direct swap (from what I've read), and it would be wider by 1 in. I'm looking for one for my 04 now.
He has a 2004, so any 99-04 would be a direct swap. A 94-98 rear would be 1" narrower (for his car). You could use a GT, Cobra, Bullit, Mach 1 -- doesn't matter.
The wheelbase widths are by model year, not model type (V6, GT, etc).
Oh yeah, just in case it needs pointed out -- can't direct-swap with a 03-04 Cobra since they have IRS. Although a guy called "Zach" did do the swap... it was quite involved! :eyepoppin https://www.allfordmustangs.com/forum...-irs-swap.html
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