Is it possible to repair back housing glass without disassembly?

Hi guys, I've checked out some videos online of how to repair the back glass of the iphone 5 and everywhere I see people pulling the entire phone apart.. I'm wondering if the glass is cracked could I not just use a heat gun and a pry tool to pull the glass off and then Use some adhesive tape and apply a new one.. From what I can tell from videos i can't see anything else holding the glass in.. Can someone verify this? Or can it be done? TO BE SPECIFIC: I am only concerned about the rear glass at the bottom of the phone, not the one in front of the camera.