You could make all weapons too large to fit on fighters and bombers, then add scale mounts to make the appropriate "fighter" weapons useable on fighters, and the appropriate "bomber" weapons useable on bombers. They would all be fighter vehicles, but you could restrict the weapons in this manner if you so choose... Take a look at those Adamant data files and the colony modules. They are massive, and you must use a Colony Mount to put one on a colony ship (which is the only ship that can ever carry a colony module, other than the Large Colony Ship
).