Need Help with 1999 Civic Si Header Install

[irocstang]

Havent been on this site for awhile and now have a 99 Civic Si that I need help, pointer and advice with how to get my exhaust to fit.

I got a header off of a friend that was on his d series motor and am now in the process of installing stalling it in my 99 civic si as the stock header had a crack. The new header is not a stock honda si header like the cracked one its replacing. Its a bigger diameter 4-2-1 header that has two o2 sensor mounting holes (one where it branches into 2 and 1 right near catalyic attachment flange)

As its an Si the Catylic converter is not included in the header its after the header. Stock o2 sensors locations are 1 at end of header near flange and 1 right in the catalic converter.

I installed the new header and o2 sensor was put in its stock location at the end of the header. Top o2 hole was capped.

All was peachy untill i tried to connect the end of the header to the flange of the catylic converter. Had to pull the catylic forward to attach but cant get a nice fit as the catylic o2 sensor is getting pressed against the undercarriage.

Now ive talked with somepeople who say to do this that and the other thing but id like your opinions too... Maybe from someone who has encountered this probelm and solved it.

From straight pipe to and eliminating o2 sensors completely and pulling cel bump from dash, to high flow cat and o2 sensor wire extendors Ive heard it all.

Id prefer to have the o2 sensors in and not have to pull cel bulb. I would really just like to know how to accomidate my header properly instead of guessing and spending cash for no reason.

Please help if possible.