A weapon how to!
Using the existing rules, a bazooka can be done. Take any of the MISSILE LAUNCHERS and attach an AMMO CARRIER so you get double the shots out of the one weapon. For all intents and purposes that is a mecha-sized bazooka. The drawback being that for the same "price" you could have two identical launchers, granting greater tactical flexibility. But if you're trying to emulate a mech from a particular show, now you have an option.