it wont work. the heads are different. sell it and buy a novi2000 or a vortech. you would need the intercooler also but it wont work regardless...if you want a roots type id recommend the saleen type V twin screw blower.

just remember when bolting a blower onto a formerly NA car, youre gonna need bigger injectors (42# preferable), fuel pump (03 cobra pump), mass air calibrated for 42# injectors (Lightning mass air works good), and have it tuned so you can drive it and it wont blow up (if tuned properly). expect to spend some dough.

nitrous would be a lot cheaper...is your car a stick or auto? if stick, id be careful about the bottle, but its still fun...if its an auto i say spray away

btw...why on earth would you get rid of an 03 cobra for a GT??? thats not taking a step back, thats turning around and running. completely backwards. and please do us a favor and not put altezzas and a fire extigusher in it. its a mustang not a honda. im not trying to be an ass, but those things look retarded.