If you're trying to save as much money as you can, and can live without the cats, I'd recommend you get XERD headers - they're long-tube equal length and get rid of the cats completely. I've seen them around for $650.
This saves you lots of money as you get high flow headers and completely eliminate the cat constraints at the same time.

 

Expect extreme resonation... which many have sold their xerds due to this. Then do not expect any gains of torque.

Stick with the high-flow cats and plenum options for best bolt-ons.

Those headers are going to be WAY too much $$ to install to be in your budget.

 

Yep... any headers you look at will probably be somewhere in the 5-6 hours of labor range. That will probably clock you for abou $400 or so in addition to the cost of the headers. IMO, stick the plenum, cats, and exhaust.

 

On the other hand you can install the bolt-ons yourself and you will be able to afford significantly more on your $2000 budget

 

what kind of gains should you expect from rt cats?

 

5 - 7 max.