FLX:
Probably would do youself a favor and drop a note to Don Boston who's the NEVCA President (Join the VCA). Known on this site as -RUNNER
don@neviperclub.org
Some of the NE boys will chime in and give you the best techs in your area, although Chuck Tator is SO good that many of the southern NE members drive down to South Salem NY for any serious work. Tubes and filter upgrades will NOT hurt the value, no question. Likely that a "known" exhaust system with HF cats will also not influence value (at least not negatively
). I'd hesitate to remove mufflers and/or cats if you are very concerned about keeping the car "near stock".