Adam,

Keep in mind that glass and resin are going to add weight to the plane. Depending an the technique this could be alot. When we fiberglass foam wings for our planes we use a vacumm bag to pull the flass to the foam and excreate the excess resin from the glass. I am not sure if there is a link that will give a step-by-step method, but you may be adding more weight then the plane was designed to fly with. Do a search in the building section and see if you get any hits.