i have been chasing down a ses light for weeks and finally gave up and went to the dealer. in have a clogged cat in bank 1. the cats are $750.00 a piece plus insatllation. they told me you mime as well replace them both because to take out the one that needs replacing you have to take them both out. i am a diy'er and would like to attempt this job but not to sure on the way to tackle it. the job books out at the dealer at 6hrs which means it will probbaly take me a full day. my question is, is this a diy job? any idea where to by oem cats for less money? or should i just give it to the dealer for $2000.00?