i have a 06 RCSB with a 5.3 in it with a 40 series flowmaster dumped..... were i am at we have emissions so i can not get rid of my cats but is it safe to have them gutted so they still look like there or will it cause a cel code bc of the O2's.......want more sound, but HATE seeing the cel on

 

You can gut them but it will throw a code for the rear 02's. Depending on your state you may or may not get away with it, if its just visual inspection you are fine but it will fail the sniffer if you have one. The cel codes for that will not affect your performance at all and if you wish you can have them tuned out.