More than six gallons. I just couldn't believe it. I really wasn't set to handle that much fuel. Fortunately I had a bolt ready to thread in the fuel line to stop the fuel. Had the rear of the car set up high on stands and I had a five gallon ready to take up the fuel. Never would have thought that wasn't enough.
If I ever do that job again I would gather up plenty of empty fuel containers, and be ready with some vise grips to pinch off the fuel line. As I recall I found the old fuel line there to be rotten and had to replace that. Don't recall the size.
The worst of it was that that screen wasn't plugged. My problem turned out as failed glow plugs. But I got a real nice rinse for the fuel tank out of it.