Hi Vincent, I'm pleased to assist you. No, these do not bolt straight up to the headers. The stock converter on this group of vehicles is a two-piece design, with a separate flange that bolts to the headers and a second flange that bolts to the exhaust pipe. The Davico 16131 is a one-piece design, so you will need to cut off the old flange and weld on a new one in order to install it. To proceed with your order, click the link below. Take advantage of our ongoing deal and limited supply. I hope this helps, and have fun shopping! https://www.carparts.com/catalytic-converter/davico/dav16131?can=CPGG4850_CSQA_20231003

Hi Dwight, thank you for reaching out. No, we do not have a pipe like that without the converter. Have a good one!

Hi Kody, thank you for reaching out. If your 1999 BMW M3 has a federal emissions exhaust system, then yes. You can use this link to go back to the item page and continue ordering the part at 57% off the regular price today: https://www.carparts.com/catalytic-converter/davico/dav16131?can=CPAP3648_CSQA_20220903 I hope this helps. Happy shopping.

Hi Jonas, Yes, both catalytic converters are included.