Well there is a reason that all the books say to nail the gun port lids open if you want them open.I have open ports, and I often broke them off on previous models while I was doing the rest. When the model is finished, many viewers open and close ports and doors when they look at it. They also sometimes break them off. That's why I make everything very strong.
But if people insist on breaking on your models... i insist upon breaking their fingers.