First here's the iFixIt guide to remove the front glass iFixIt guide
In this case you shouldn't need any adhesive as the glue Apple used is heat activated. Once you have taking things apart make sure not to touch the glue areas. Then re-assemble and where the step had you using a heat gun you'll do it again and this time press the glass down evenly with a gloved hand (so you don't burn your self from the heat).
So far I've replaced about six cover glass panels and have not needed to add any glue.
If you do find the glue is not reactivating for some reason, you could try using a glue gun adhesive.
Ok so you think once I go through this process and using the heat gun and what not I should be ok? Makes me nervous because the bottom of the glass is no longer stuck to the bezel i can go as far as to stick something in there, thats how loose it is...Wouldnt a glue gun adhesive make it too permanent? or would that just loosen up again with the heat gun? Thanks