Thanks Ronw you have been a tremendous help. It appears that there is an air leak at the flanges of where the exhaust bolts to Cats. The welds are cracked. I am gonna see about getting this welded and try clearing the codes again.
The vehical was only giving one code but I rechecked it yesterday and I now have same codes I had before I change the Cats. P420 and P430. Which in the book states that its both Cats. How can this be. I have brand new Cats. A mechanic at the dealership told me to check the exhaust to see if I may have any exhaust leaks. Could this be a possibility? I don't know what else to check other than the sensors maybe.