Im ready to upgrade my 2002 gt auto so I was thinking of going with magnaflo catted x pipe with magnapacks catback, accufab tb-plenum with a set of 4:10 gears and a tuner. about how much HP should I get with these I already have a JLT cia on it. and should this be a good start.. Also if I go with a off road pipe and a tune can I still pass inspection in ny.