Will this wheel fit?

[PhillyCobra]

Interested in close out sale for SSR GT7 at Tire Rack, 18 X 9.5. Am concerned offset is only 21 mm, whereas stock 9" wheel is 26 mm. Will this fit, especially in rear with IRS bolts, with 275/35/18 tire?

http://www.tirerack.com/wheels/Whee...odel=Mustang+Cobra&autoYear=2003&autoModClar=


Thanks.