Way back in the eighties (specifically 1989), back when the battletroops game was still a thing, there was an "open hatch" rule in the Battletroops book that allowed a vehicle's commander to operate a pintle mounted support machinegun. Which, of course, also assumes that combat vehicles pretty much always had such a weapon on hand.
I'm not going to ask for rules covering its use or anything (I'm not even on the right board for that). My question is should this reference, which has not been repeated elsewhere to my knowledge in the subsequent so many years, be considered to hold some canon weight?
Do combat vehicles have support class machineguns on hand?