Almost there.

I had thinned some Poly Crylic with water and alcohol to try on this plane. I used it to apply the fiberglass cloth to the fuselage. Two coats where I usually use three coats of un thinned stuff. Then I thinned some Spackle

with the same thinner and brushed a coat on the fuselage followed by a light sanding and a third coat of Poly Crylic. Then I installed the fuel tank and wiggled the nose gear in place. The engine went in fine as it has been in  before but without the muffler. I lined all the holes in the nose that take the needle valve and tools and screws with pieced of brass tubing. That protects the wood and paint from abuse. I weighed it and got 46.9 ounces before covering and paint. So it should land around 55 ounces.
  I tried a different formula for the epoxy and micro balloons fillets.The 5 minute epoxy I always use set up a bit too fast in these warmer temperatures and the 30 minute stuff is way too slow. I tried adding 25% 30 minute hardener to the 5 minute hardener and was able to do one wing root all the way around and the stabilizer on both sides with time to spare before it set up. Just for giggles I used the 30 minute resin and 5 and 30 minute hardener mixed as before and got the same results on the other half of the wing root. I figure the only difference is the hardener. Now I need to spray on a coat of primer and fill the low spots before covering the wing and stab and final color paint.