Yes or you may have a blue and white power antenna wire. This will also give a 12V out. Its likely that you have this, look for two wires coming out of one pin.
and cal91, yeah sounds like a good build. and yeah sound deadening is possibly the best way to spend 100 quid on audio. You will notice a massive difference. And if you wire in the sub its one job less to do in the future.
This stuff is great:
http://www.caraudiodirect.co.uk/second-skin-damplifier-bulk-kit.html
the blue and white wire wasnt on the iso block so wired to to stereo remote and its working. thanks for the help