Ed,
Are you installing the super charger yourself or having a mechanic do it? I am sure its a very involved process. I have a 2010 Roush Mustang with a Roush super charger. I am at 435 HP and 400 ft lb of torque. Your 07 has the same 4.6 V8 I have so I would expect you would be over 400 HP too. Have you ever driven a super charged V8 Mustang? Im sure you know that SC cars are really quick because of how they develop boost. The power is immediate. Good luck with the install. Once its done... hang on ! Let us know how it goes
Steve