That's awesome. Very retro, reminds me of the arming screen from Hornet Korea. The clipboard was a staple of 90's sims, I'd love to see it used as the background of any in-game options system.
Currently arming happens outside the pit, you walk around selecting pylons and the ordnance you want to load on that plyon. Rockets are loaded into zones in a 3 click cycle. At the moment rocket models aren't visible when loaded but once they are it should be quite an intuitive system.
You can see the loading system in this video @ 1:15
http://youtu.be/Y6ILqIQDaioThe clipboard would be a great way to arm without leaving the pit which would be useful as it could be tedious to shutdown and startup each time you re-arm.
Cheers