Well, I had the best of intentions to write a rebuild report! Flew the repaired plane today!
The original owner repainted it after the repairs and it looks better than when I got it! Had to move the battery from over the gear to the rear of the canopy to balance. The CG is pretty close as it took two clicks of up; inverted flight takes light down pressure on the elevator, just like before. Still need to go through the trimming procedure but I was too shaky today!
Basically I followed the advice to carefully fit the pieces together, then use CA to hold it all together. I used a straightedge on either side, and the undamaged canopy to keep it all straight. Flight characteristics say I was successful. I replaced the front part of the belly with balsa with thin fiberglass veil over top. Used the veil on the forward fuselage sides as well. Plenty of microballoons and epoxy to make it look good. No idea how much weight I added since I don't know the original weight.