mount it in your glove box if you don't want people to see it... or some people take out their radio and put it there.
the vafc is just a tunning device, without dyno tunning it won't help... then ur just going off the "butt dyno" i've seen it make some significant gains but you will need tunning. and like pappous said with just basic bolt ons it wont help, then you would be better off just shipping your ecu. good luck in what ever you do