test pipes and cat back exhaust

[vikesfankevin86]

I have stillen cat back exhaust but that is all I know because I got the car with it. I have the cats off the car but I believe they just cut them out and put a piece of pipe there to replace them. I wanted to get test pipes and was looking at this. http://www.importpartspro.com/sz3altepini3.htmlShould I order these and do I need to do the "cone down" accessory to make it fit to the cat back?