But since yours is already in, buy new glass. Then smash the old glass with a hammer. Wear leather gloves and goggles and use a small chisel to remove the adhesive holding the glass chips to the backing plate. The new glass will come with sticky back, but don't rely on it. The glass will fall off the first time it gets cold. Once the plate is clean, apply some black automotive RTV to the outer edges of the backing plate and press the new glass into the sealant. Hold the glass in place with masking tape until the RTV cures. That will hold it in place forever–or until you break it again.

Rick

I'm a retired ASE Master/L-1 Technician. I still keep current with the latest automotive technology. Visit my blog for cool articles and TSB's: http://free-auto-repair-advice.blogspot.com