Hey pal, on our cars we have 4 cats. Two on the header and two on the secondary cat pipes (connects header to muffler). The problem with deleting the header cats is that it will throw codes. However, the secondary cats don't have any O2 sensors. They're just extra thumbs really. If you want to get rid of them I recommend buying the Fabspeed secondary cat delete pipes. Sell you're old ones here if they're in good condition and call it a day!
Where are you located in Canada?