I'd build up the Dura Ace set if you don't mind 36H, and try to swap out the freehub body with a 105 freehub. Making the Dura Ace 7 speed and HG compatible.
But bear in mind....one can't really remove the freehub body without the hub laced and built up as a wheel.
The hub shell needs the spokes to secure it in order to torque off the retainer bolt.
Mind 36h? I'm old enough that I think 32h is new-fangled...
But swapping the freehub bodies!??!?! I didn't know this was an option! I understand it would be tough to get off, and thus lacing it up first makes sense. Are you certain it would fit / be interchangeable? A true 7-speed DA hub would be a bit nicer than 6-speed. Thank you!
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1959 Hilton Wrigley Connoisseur (my favorite!)
1963 Hetchins Mountain King
1971 Gitane Tour de France (original owner)
* 1971 Gitane Super Corsa (crashed)
* rebuilt as upright cruiser
1971 Gitane Super Corsa #2 (sweet replacement)
1980 Ritchey Road Touring (The Grail Bike)
1982 Tom Ritchey Everest
(replacing stolen 1981 TR Everest custom)
1982 Tom Ritchey McKinley (touring pickup truck)
1985 ALAN Record (Glued & Screwed. A gift.)