I just purchased and installed the Polaris (MBQuart) Audio visor. This unit comes with 4 switch blanks for your use for other accessories. Anyone know how to route wires inside the visor to utilize the switches? I see no access panel or anything to give me access to inside the unit. I can't imagine I have to drill a hole in the top side. I've emailed Polaris and MBQuart and can't get an answer. Apologize for my ignorance.