Sorry if this is a dumb qustion but i know absolutely nothing about head units. My question is if i get an aftermarket head unit, will i lose the 6-disk cd changer from the shaker 500? If so, are there any aftermarkets that have 6-disk changers?

 

They make them but I've seen more options in the single units. You could always go with a trunk mounted CD changer but that is so 90's

Here's a unit by pioneer for $499. It's a shame to have this big of a screen and no navigation though.
http://www.crutchfield.com/p_130AVHP....html?tp=20217