i just did this to my son's grand am. Bought a r/defroster repair kit (that included tabs too) If yours is all goobered up from previous attempts at fixing it just put the tab a little bit over in the tab area of the grid. His car had a tab grid arfea of 1"x2". I took 000 steel wool and LIGHTLY cleaned the area. Follow the kits directions and the tab should glue on. Hold it in place for about 3 minutes.

The key to these repairs is to NOT reconnect the wire to the tab for 24 hours as it will actually weigh tghe tab down causing it to come loose. The warmer the glass is is better. We pulled it into the garage and heated it up with a hair dryer before gluing it on.