I have older Furuno nav units on a 2004 G/W 330 Express. They're mounted in the pop-up electronics enclosure. For my use, I don't need to replace the entire installation, but I can replace one of the units that has developed a problem with the display. Replacing with an identical rebuilt unit looks pretty simple (it's on the network), but the question is how to get behind the enclosure to remove the mounting screws. Has anyone had experience with this swap out...?