You'll have to find a way to remove the whole head unit.....mine was a jensen....popped the trim ring off and removed 4 screws and whole unit slid out so I could get behind the unit. Normally you can release the wiring harness, remove antenna, etc and then you can take the whole head unit right out. Someone with the same unit as yours will speak up and help you out.
2012 Eagle Lite 298RLDS
On Permanent site at Gillies Lake, Bruce Peninsula