Downpipe is not necessary on almost all headers. I think ZZP is the exception but i cant remember. Just get the speed daddy headers and stock catback and call it a day.
Is the exhaust from ZZP stock? I think someone said it was Maganflow?
2001 4dr Black GTP Stock and staying that was... maybe
1997 2dr Black GTP Open Cone, GXP Rims, Black Headlights, ZZP Headers, ZZP Cat Back, Bunch of suspension parts from ZZP, ZZP 10.5MM plug wires, Autolite 605s, Overkill Tune