Regarding antennas, the Skyraider thread has a ton of useful info, particularly pages 5, 9, & 18. Be sure to somewhat ignore the VNAF machines as they will have an antenna configuration difference.
viewtopic.php?f=3&t=47875The canopy thread is here:
viewtopic.php?f=3&t=51642An antenna discussion, particularly on the E, E-5, and G models was here:
viewtopic.php?f=3&t=52685&hilit=SkyraiderRegarding chaff/flare, seems like I've seen that photo, but the word "chaff" doesnot appear in the 1971 A-1 Dash One, nor does the word "flare" or "dispenser" (in that context).
I have also not seen the speedbrake petals extended for maintenance, although one would assume it is plausible, although more likely to be done on jacks, I would imagine, due to the travel of the ventral petal.
As far as maintenance with ordnance, I guess it depends on the scene you hope to portray. I'll leave this to Hook and the other vets, but I can only imagine a last minute abort where there was no spare and the ground crew was called out to troubleshoot a specific problem in an effort to get the plane launched on a mission. The problem with this is that there is nearly no plausible scenario where the entire cowl, speedbrakes, etc would be open to the extent I gather you hope to display. One side of the cowl, sure, but much more lends itself to heavier maintenance that would be done on an unarmed airplane. An unarmed plane, BTW, might have covers and streamers on the cannon barrels. Keep us posted!
Ken