Yeppers, I remember it well. In early 1965 Chu Lia Viet-nam, we used to escort the tanks on patrol and they had a few Ontos that would be there. Some of the roads and bridges would be to small for the tanks to cross but the Ontos was small enough to cross, so we would escort them into some of the villages. Sometimes in combat they would be perched atop a hill and would fire tracer 50mm at their targets and once they spotted their target then they would cut loose with all six 105mm barrels at the same time. Truly awesome sight. I stopped seeing them after about 3 or 4 months.