Well, maybe something can be arranged. I like the idea at least a vehicle mounted mortar of some kind being able to be mounted. They wouldn't do damage to a battlemech type of a armor but it be useful softening up infantry formations.
Guys, don't roast me I don't have my books but I do know that man type mortars and stuff like that would be light enough to be mounted on a battle like they're not in the tonnage scale versus lesser than that