[gonzo]

> Venturing Crews and Sea Scouts, both of which are part of BSA, have been co-ed for a long time. My initial research was not particularly fruitful, but I think that they've been that way since their respective inceptions.

Venturing Crews and Sea Scouts were both part of Exploring in 1969 when the program went co-ed.

> There's also no gender-specific leadership or structure.

There are, actually. Quoting the current edition of the Guide to Safe Scouting:

"Two registered adult leaders 21 years of age or over are required at all Scouting activities, including meetings. There must be a registered female adult leader over 21 in every unit serving females. A registered female adult leader over 21 must be present for any activity involving female youth."