ok i was also confused as to where to install the injen cai. but i have a feeling i ended up doing the same thing as your mechanic did. the intake is behind the front bumper for me. i will get pics up next week when i have time

the sound is very good, but sometimes it sounds like the stock intake unless you go WOT. but when revving the engine with the clutch in i can pick up a nice induction hiss