ok. i'm setting myself up for my incoming empeg. yesterday, i installed my temp_din_deck/amp/sub with the wiring. i got a hsu 1202m sub connected to a hifonics zeus z700 in a 99 civic coupe.

The problem is, the sub is cylindrical... and is rolling around the trunk whenever i accelerate and decelerate. Ideally, i would've just strapped it on to the back of the back seat, but the amp was placed there...

what should i do to secure it down? i've been suggested with bungee cords and anchors bolted floor.. that'll keep it still, but wont deter a thief from unhooking and taking. if someone was ever to get into my trunk... i'd like to make it almost impossible for a thief to get anything quickly and require them to actually steal my car. the amp is bolted down, and i want some of the same security for the sub. any suggestions?

thanks