i'm running the exact same setup as you, minus the box resonator and hotdog. where the hell did u get the box to fit? if i put it on, it would be hanging way too low, or touching the tailshaft. mine is all mandrel bend, so it kinda takes up alot of room with no harsh bends.
i reckon maybe this guy got the reading wrong, coz the revs didnt increase gradually, i remember punching it a little between 3500 and 4800, coz i was using my left foot, and was only half in the car
although it would still be over legal limit, i have no doubt.