Hi, I have to replace the glass portion of the right side mirror, I found a webpage that describes how to remove it, (Ram built in June of 2007 & has the lock tab that you press in to slide the mirror backing off the mount). I located the tab & depressed it, but wasn't able to slide the backing off. It seems to be stuck, has anyone had luck removing it & am I missing a step? I was hoping to just replace the glass & not the whole backing assembly. Thanks for any advice in advance.