(Re)Built Ford Tough: A Flathead V-8 Rebuild Time-lapse
I saw an old Ford pickup for sale in a used car lot one time. It was an early 50's model and it had a flathead V8 engine. The guy running the lot wanted to show me how smooth the engine ran. Standing right next to he asked if the engine was running. I said no. He opened the hood. The engine was spinning merrily away, quieter than a kitten's purr.
It looks like a lot of work, but if you know what you are doing, and you have the right tools, it doesn't take that much time. Maybe a week if you are working by yourself in your garage.