My favorite non W2 header is the Hooker 5303 which is no longer made. They couldn't sell them because A) they are slip together and 2) everyone says they are too big. Neither of which is true.
Good, cause I got a pair! Never gonna fit a >66 A now that I modded them for a 65 but the slip fit collector is genius: You snake and screw the tubes all in there with the motor already in and then you barely bolt them on. Next you slide the collector onto the loose pipes and then tighten the flange bolts. The system hangers wont let the collector slip off and you got a superior big *** pipe header for your stroker or high winding LA. Pro-parts headers for the B/RB A crowd had tabs that overlapped and took a lock bolt, just tack weld those on if your scared the collector will blow off. If you think you'll have a leak, just run a thin smear of ultra copper RTV in there, seals it up good. Multi pipe headers are also easy to mod as its just one pipe to take out and ding or shorten/bend/? and then you can slide it in and see your results. lather-rinse-repeat.
