My SD headers just came in today and I have to pass emissions by the end of the year. Therefore, I need to keep my cat. Since the only way to do this is to weld it ( I think), how would I go about that? Can I just weld the rear headers to the cat outside of the car and then drop it all down through the hood? Or how would I go about it? I'm looking to install them on Sunday so answers are much appreciated. Thank you.