I can see something like the following happening in basic workshops: -
And there's plenty more where that came from...
Images from this site: -
https://philippinestoday.blogspot.co...ood-armor.html
And even improvised fighting vehicles such as trucks given armour and carrying a field gun portee-style like this: -
Image from wiki: -
https://en.wikipedia.org/wiki/Port%C3%A9e_(military)
But as mentioned in my earlier posts, I think for armoured vehicles, replacing the turret or main armament with something the vehicle was not originally configured for, would take skilled personnel with a proper workshop (e.g. one that can do repair & refurbishment levels of work)