Remove the cap and wire directly to the amp. I would also ask for my hatch back!
Seriously though there are much better mounting locations in the Z than where the amp is now, plus you won't have to give up your trunk. It would be a shame to put a big scratch in that pretty amp. Try behind the drivers seat if you don't want to spend a bunch on a fancy install. I would just get the amp out of there very heat score for a thief.