I've just upgraded my existing RA2 to RA 4 to be able to use the control center more efficiently. Can I upgrade my rear wiev mirror as well to UConnect/auto dim mirror. If I don't upgrade it, I need to purchase and use 911 call emulator plug which cost around $50. The upgrade mirror is $65 from LKQ. I've just checked harness for my existing mirror. All the cables ready to plug. Please advise? Thanks!