I had a little time available between work trips away, so I decided to assemble and Proseal the Bulkhead Unions on the root ribs. The manual suggests you do this after rib installation, probably to ensure easy access to the rivets adjacent to the union. But I’ve got a thin-nosed yoke which will fit.
I gently nipped up the nuts, having applied Loctite 565 to the thread just as a double protection against leaks … but if the inside joint is sealed correctly fuel should never get up the thread, so probably not required.
Masking once again kept the angry Proseal under control!