There is a great use for Gorilla (polyurethane) Glue - and that is to sheet foam wing cores. Since it expands to fill gaps it works great bonding balsa and plywood to the cores, and you no longer have to pre-glue the sheets together to make one large sheet - just tape them together and the glue fills in the gaps (but you do want to have a good fit between sheets as a general practice). It's a lot easier than using double sided wing tape, sorghum or contact cement.

Hogflyer