The indash radios Fleetwood uses are not double din radios. A double din will fit, but you have to cut about 1/4" more from the top or bottom. I just replaced the one in mine, used a single din Pioneer, and used a Ford adapter, Metra part number 99-5806, or 99-5802.
Here is a thread on another forum about replacing it.
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2007 Fleetwood Excursion 40E Cat C7 350 HP
2007 Chev 2500HD D/A Long bed CC (Yes, it is my TOAD :B)
2011 Toyota Tundra
2013 Jeep Wrangler Unlimited Sahara (Backup towed)
Gone but not forgotten, 2008 Jayco 299 RLS