What headers work, and what don't?

DIfference is 5/16 flange vs 3/8 flange, Material & thickness of tubes / collectors...73 is the widest A body made so headers are not as BIG of an issue as on the 67 - 69 or even worse on the 64 -66...... check out the specs and buy reputable or you will be replacing them in a year or two...also fit them THEN get them ceramic coated.... I do not use the three bolt collector flange they are a PITA....try the stainless band but that means cutting off the flange retainer on the end of the collectors...I like them becuse they do not come loose ( if dun rite) and seal better ALSO much easier to remove & reinstall if necessary. in short YES there is a difference a noticable and notable one