I'm not sure since the OEM CD changer in mine still works.
I do know that just because there is a standard, it doesn't mean the mfr follows it. I have a 2.5 DIN head unit in my RV. Go figure. The head unit that came in it was specially made for Coachmen by Unisonic.
BTW, the front end on the RV is an E450 so I blame Ford![]()