First of all, thank you both, as I used your experiences and photos to restore an ancient #3 last week. It was a craigslist score and even has the Japanese stamp!
I'm kicking my self for not documenting the process, but it wasn't much different from yours, just less work. The only crack in the egg itself was in the bottom and I JB Welded it and covered it with furnace cement. The firebox had several cracks which I gave the same treatement, but it appears that the cement doesn't adhere well to the JB Weld. When heated, it appears to bubble up. Did you do anything to prepare the surface? I let the JB Weld dry for 24 hours and did the same with the furnace cement.
Anyway, it's a really good cooker. Surprisingly, very little lump, draft and time was needed to get it over 400. The wife wasn't too pleased with the addition to the family, but the beer can chicken in an hour won her over. I'm really impressed with this 20+ year old cooker.