I plan on buying some new front speakers for my Corsa B. How do you get the door handles off to get in the tweeter encloser? I've removed the screw at the bottom but cant get it to come off. How are the tweeters held in? Also where can I mount the cross over network? I dont want to have to drill into the car, or at least anywhere visible so I can sell the car on. Thanks In Advance Andy M