Take out the factory screws and miss-match the screw types around your subs and bolt it to the car. That way if they want it .. they have to piss around with a few types of screws to get your subs out .... piss around with bolt that holds the box down and then steal it... trust me, they don’t usually want to be around that long.

then you'll most likley have a fun time removing the subs they drive a screwdriver into when there pissed off...

I put a personal alarm in the trunk. You know the ones that you use when you go walking at night? When the pin is pulled it squeals away and it's loud! This is mostly a paranoid thing .. so if they have a way around your car alarm .. they will never see it coming but they will surely hear it and hopefully so will you with enough time to chase them away with a shotgun in your hand

I like this idea!!!!

Anyways, this is my two cents. Take it for what it's worth.