Im looking to add a CAI and tune to my 2007 mustang gt. I have no experience with working on cars. Which combo should i get that will net the most HP gains and how easy is it to install CAI and tune the car? Also this might sound ridiculous but how does a tuner work where does it plug into a mustang to program what you want from it? the only other mods i plan to do is o/r x pipe with flowmaster 40 series will I need to tune for just the CAI or will I need a tune for the exhaust changes also?