i have a 99 civic ex coupe...

so how do i do it? start from underneath? start unbolting shit?

i need a torque wrench?

etc......

 

Have some WD-40 and spray every bolt you see except the O2 sensor. The heat shield is easy to take off. If I remember there are 9 bolts on the head, one in the middle infront of the block for support, 1 near the bottom for support, and 2 near the flange for hanging support. Then there are of course the ones on the cat. Start with the heat shield and then the bottom. End with the top bolts. I had my car raised and pulled the header from underneath. I took out that black scrape gaurd the goes on the bumper for easier access. You can unplug the O2 sensor from the wiring harness and un screw it later if you want. Then just go in reverse with your new header.