got my long tubes in and has 1 hole in each of the headers for the before the cat O2 sensors, and i went 3 inch all the way in to an x pipe and then dumped right after alxe no tips with 40 series flowmasters... (no cats) what do i do with the after cat O2 sensors??? no holes to put them in and have no cas now so even if i did.. it would read wrong.. what do i do.. thanks for the help!!!

 

Neatly tie them up along the inside of the frame with cable ties. Normally I would say disconnect them but that may lead to corrosion on the terminals over time.

...Assuming you already have the rear O2 DTC's disabled,...correct?

 

I would tape up the plugs, pull the sensors. I don't like having them underneath the truck just hanging around.