If you remove the cluster, you maybe able to get the fuel gauge to come back around by holding the cluster upside down. The needle may come back for you or you can remove the lens and move it by hand. This may work for a while but most likely will happen again. The problem is the motors that control the gauges including the speedometer. You can have the unit rebuilt, you have to remove it and send it in. Here is a website that can do the work for you. They list a 2000 Lesabre, but that can do the 2004 as well. You may have to call for more information for your 2004.