I'm thinking of doing this and putting a black grill cloth to cover the hole in order to allow more bass to come in through the trunk. I'm not sure if the back seat is backed by metal though, if it is then it might be more trouble than it's worth.

If anyone's done this please let me know.

 

The back seats do have metal support...

 

Oh well, there goes that idea.

Thanks.

 

just cut it neways..