I remember watching a video of yours but I don't remember what your back deck looked like. Did it have factory speakers or is it completely sealed off? If there were speakers there you'd be able to take them out and it could let some air go into the cabin. I doubt you'd want to cut anything right? I have a similar problem in my suv, it's louder rear firing but I'm going with 3 12's and I have to fire them up. Lucky for me I don't have anything blocking the subs.