yes you do have to do all that...that is if you want to stay legal. I plan on doing that anyway. When I had my exhaust done I was dumb and had aluminized steel put on for the piping. Well around here you deal with rust so I'm gonna have to be replacing that soon. Might do the header, cat and custom piping done then.FFighter'97dx said:see the problem is that you can't just replace the headers... the headers and cat are one piece on that car... therefore if you replace the headers (go with an ex header setup) you also have to buy a new cat. and extend the o2 sensor. damn dx,lx,hx motors... i run into s**t like that all the time with mine