There is only a few set of headers they make for 67-69 Camaro/Nova. I called them direct and spoke with a guy and told them what headers I wanted and what flange. There website has hundreds of different headers flanges to choose from in .PDF file format with all the dimentions you need.. And they will put any flange on any header for nothing. Its like having a custom header shop at your fingertips and for what they charge its not worth firing up the welder. They might not make the best performing header but you can put good collectors on them to wake them up. I also asked them to not weld the collectors onto the headers and they just sent me the collectors seperate and a kit to make them slip on with the bolts and brackets. And they send you trick bolts that are 3/8 thread and take a 5/16 wrench or socket for tight fit applictaions. Ohh and a set of gaskets for whatever flange you choose. Nice guys to deal with.
The headers fit perfectly and no custom wrenches to get the plugs out. Nice stuff.