What is preferred scanmaster 3 or G? Im leaning 3 but wanted to hear from orhers.. where & how is best place to mount so it doesnt look gaudy, still visible and doesnt leave a mark? Still need a boost mechanical boost gauge or can u just use scanmaster for boost? Im getting a 2 bar velosyty chip and forge wastegate to lock in 15#'s boost, factory gauge will still work is that along with scanmaster enough to read boost accurately?