Ahhh, you're using WBPU...

I'm using Zpoxy.
By the way, I weighed the wing panel prior to glassing and after. Glassing the top of the wing (3/4oz cloth and un-thinned epoxy resin - un-sanded) added 38grams to the wing. So I figure less than 3oz to finish the entire wing.
FYI a roll of Monokote weighs 2.6oz (26"x72" roll 13sq feet at .2oz/square foot)