the o2 part sucks. i ended up getting a custom dp made for my sd headers, so i had them install 2 bungs in the curved pipe for the o2 and the wideband. then i cut the o2 plug off the cars harness and made it 3 foot longer and re routed it down the strut tower to the rack then the dp.

some shops have a plug you can put in the unused o2 bung to seal it off.