Go to spdexhaust.com good products very knowledge, you will have to use W5 flanges to swap between the heads,also the flange will be on the upper side,omn the w2's and you will have to grind the part of the flange to get the sparkplugs in and out any question or if i can help let me know,have w5 headers on w2 race heads in 72 demon
Thad Shiers