Hi. A south american gun: Citer (also called Citefa in some sources) 155 mm L33 M77/81.
The first one is as it was shown in 1996 when the Group 101 was renamed. It is shown with the standart artillery tractor, the Fiat 6605, both in olive drab.
The second one is one of four guns of Grupo 101 during 1982 Falklands War. It was camouflaged with two green shades. The little Unimog appears an odd choice for the primary mover, but it was the only truck aviable in the late date of the arrival of the guns to the islands. The red elevation wheel looks odd, but is painted in that way in the restored gun of the Muckleburgh collection. Finally, one of the 12 guns of the Croatian Army, with TAM 150 truck. Cheers.
Credits: I borrowed Glorfindel´s TAM 150 and Unimog 404. And the croatian gun is painted in the same shade of green of the yugoslavian truck.
Thanks Pegasus and hudavendigar for the ideas for the plastic windows in the canvas!