I was wondering if it would be a lot cheaper to do a cat delete than get headers. I already have around 470 hp as is and was looking for some more aggressive sound. I didnt want to get rid of the mufflers either.

Anyways, just cutting to the chase. How much would a cat delete cost me for a 3v mustang?

 

The most relevant question is whether it's legal to have no cats on your car where you live. Your car could fail a vehicle inspection.
If that isn't a problem, you could swap in an offroad midpipe and have the ECU retuned to disable the rear O2 sensors.

 

If you do have 470 horsepower with your 3 valve, you must have a supercharger. I wouldn't touch anything

 

Assuming the car is only trailered to tracks for offroad use only, and s only driven on closed roads and tracks, it is perfectly legal... but tampering with the emissions control equipment for a vehicle driven on US roads is a federal crime. An offroad x-pipeby pipes runs $166. https://www.jegs.com/i/JEGS/555/30608/10002/-1
You might be able to get your local muffler shop to weld up something cheaper.