Yep, that adapter is the missing link! That'd be the upper of the two adapter cards and lower of the two adapter cards in all four multiple adapter configs on that page.

trag has the connectors, but they're most elegantly configured in the "Wrong-Angle Adapter Hack" that bbraun and I (and many others before us) have been doing to clean up klugeish configurations like you see in the (NO SOLDERING REQUIRED) configurations on that page. The "SOLDERING REQUIRED" config in the middle diagram shows the "Wrong-Angle Adapter Hack."