Re: Speaker Replacement
Have you got an electrical multimeter? If not go to somewhere like Maplins as they sell them for less than a tenner (perfectly good enough for what you're going to use it for). Put it accross the connectors with the head unit on and the speaker disconnected. If you get a positive reading the positive probe (the red one) is on the positive speaker wire. If I remember correctly you should get about 2 volts. Be ready for the fact that each door has different colour wires to the speaker!
Thats how I did mine and they are hunky dory!
See the hidden rear door handles on the new Civic: That's Honda leading the way in design...