ok, 95 5.0,jba shorty headers, no cats, flowmaster am thunder catback, cut off old nasty tailpipes, ordered american muscle 2.5"ss tails, because the drone is killing me, been to three shops that tell me i need a whole new exhaust custom made to make tailpipes work.??.... should i be havin this much trouble with this?? do i need flowmaster brand tailpipes?? whole new catback?? any suggestions on what i can/should do?? please help. thanks