Removing the door panel will uncover the factory fuel door wiring clipped to the plug.
If you're lucky, you can pry out the plug from the top, and the wiring will come out with it - without having to pull the door panel.
If not, you can pop out the trunk release from the top and try to fish the fuel door switch connector out the hole, or just remove the panel:
http://www.crownvic.net/drock96marquis/95-02doorpanelremoval.htm 
