install is just 5 bolts and unscrewing the o2 sensor....fairly simple....for the cel issue some test pipes come with a built in o2 sim or you can make your own for like $5..... use the search function and you should be able to find the how to

 

[QUOTE=svmtbman,Mar 17 2008, 10:41 AM] Would adding a test pipe to the stock exhaust make a noticeable difference in sound and power?