Thats a very achievable goal man, 400hp is pretty simple with all 3 power plants. The 03/04 may be the most fun imo But I love the mod motors. I am lucky not to have emissions here in FL. My Cobra still has all the options leather, power seats, a/c, p/s. Im not a fan of removing all the luxuries. I like to get in my caar and take a drive. It will be able to drive daily and do some Mustang cruises (running on a different map of course)
I do know tho... Since my family and I are mostly from TX. theres ways to "pass" emissions lol.