Go to a windshield or your local glass shop. They can do it in 5 min./$5.00 and it will last ,or buy some cheap glue at an auto related shop and pay up to $12.00 / 1/2 ounce and it will never stay up.
The best Glue I've used was Loctite (metal/glass adhesive. Now this stuff might take the glass with it if you should ever need to take it back off.
