The USAF purchased several polish M-28 Skytrucks - designated as C-145A - for light transport and liaison duties. Their robust design and ability to operate from short landing strips madem them ideally suited for support tasks for AFSOC, the Air Force Special Operations Command. To fill the gap between the small, unmanned "Predator"-drones and the big AC-130U "Spectre" gunships when doing fire-support for SOF-missions, the idea of the "Mini-Spectre" was born: Transforming the C-145A into a Gunship, designated as AC-145B.
You will see the building-report of such a model in 1/72.