Track or not you need some good suspension gear if you are going to build a mean machine. Spend some money on some good coilovers and maybe some strut bars first.

You will need a 3" mandrel bent exhaust to start off with. Abit bigger if you wanna throw the snail on her.

Then its really up to you on what power figures you are after, NA or Turbo is really your choice, but since you have already purchased your headers I guess its NA all the way.

My thoughts on the very first engine mods after headers and intake is a HD clutch and lightened flywheel.