I had not known that they ever used Zuni rockets on an A-1. The Zuni could replace AIM-9's on launch rails on aircraft such as the F-8, but fell into disfavor when one fired prematurely and caused extensive damage to the USS Forrestal, I think it was.
The other A-1E has bombs with fuse extenders so to allow them to burst above the ground and provide better anti-personnel effects.
Note the difference in the AT-28D versus the T-28B. The T-28A and B had factory-installed provisions for .50 cal gun pod, small bombs and rockets to support training, so it was simple to use them as-is for COIN. Note that the AT-28D has the guns faired under the wing; the ammo was inside the wing and that provided much more firing time than did the 100 round gun pod of the trainers. The AT-28D also had reinforcements to allow additional stores positions. That munition that is on the outer position looks like the rocket tubes provided with a Hawk P-51D kit but in reality is a Cluster Bomb Dispenser (CBU).
