One factor I haven't noticed being mentioned is WHERE the fighting is taking place--is it in the crossed and re-crossed continental battlefield of Europe, or is it in a somewhat-devastated but not by armies area, like most of the US or Canada.
The prevailing available firepower that a vehicle might encounter is one of the factors that will drive a locale to generate 10-20 guntrucks over one relatively invulnerable but resource-hungry back-from-the-boneyard M48. Something that has a reasonable chance of surviving a hit from a relatively easily-available anti-tank munition--say, a 40mm HEDP GL round-- would seem to be the lowest common denominator. Just how many LAWs, Recoilless rifles, Carl Gustav's, bazookas, or RPG-7s are floating about the area will be weighing heavily on the defender/refurbisher/road-warrior' mind.
And then you have the home-grown MRL system hatched from PVC pipe and homebrewed propellant & warhead filling, as described in Urban Guerrilla...if you're smart enough to make them, is your predatory neighbor also that smart? Or smarter? Shaped charges are not hard to make, kids!
