Being a former US Army Indirect Fire Infantryman, I know that most mortar systems can be transported by almost any wheeled or tracked vehicle the Army has to offer. I spent the most time with 120mm mortar systems mounted on specialized tracked vehicles. At the time that I served, these were the largest infantry operated mortar systems at the battalion or regimental level. Trust me, if our tracked vehicle was disabled, we would easily dismount the entire system (mainly tube, bipod and baseplate) and essentially "throw" it in the back of a Humvee (HMMWV). Any ammo that didn't fit would be redistributed between the other gun tracks and or stored in available space in other transport vehicles. Needless to say, we had a combat effective 120mm mortar system transported by a single Humvee including ammo and 4 infantrymen.
I also know that many 81mm mortar platoons transported their mortar systems and crews in Humvees. Although, some 81' platoons did have to hoof it when traversing through areas only accessible to light infantry.
If a major point of this game is to be as realistic as possible, I too would like to see vehicles with the ability to transport support squads. There were times, in the Army, when my platoon had difficulty keeping up with the pace of battle and we were mechanized by default!
