It was an exciting day.
First of all, I'd bought a refurbished Lightspeed headset, but it had arrived with all the refurbished parts just missing. A brand new refurbishing set arrived today, and I installed that. Just need to test it now.
Then my Sky Cowboy helmet showed up, so I spent a little time installing the David Clark headset into it. They don't have instructions, so we took a bunch of pictures while doing it.