I have read a few threads about IB and looking through below thread, a spare JL 12w3v2 sub I thought I would give it a try to see what kind of difference it makes.
http://www.e90post.com/forums/showthread.php?p=13123392
Following the above guide I set about removing the centre armrest and plastic cover and I was expecting it to be a plastic backing but on mine its metal
Slightly stumped as I dont have any metal cutting gear, has anyone else come across a metal plate rather than plastic?