Applying the epoxy filler
Once the shape was refined and as smooth as I could get it I applied a slurry of one part epoxy to one part 407 light weight filler to the entire surface.This step fills in the open cells of the foam and will help give the fiberglass a better surface to bond to.

I found some good articles on composites and lay up techniques at EAA which is the Experimental Aircraft Association. http://members.eaa.org/home/homebuilders/building/composite/articles.html

I applied the epoxy with a standard plastic epoxy spreader. You will have to do some sanding after it hardens to remove the high spots and ridges. You might also need to fill thin spots, dents and voids with a second coat. I probably added some unnecessary weight by trying to get it too perfect. The epoxy skin coat seems to add quite a bit of strength.