I found advice (last year) for disconnecting flex line on top of injector pump and forcing air in into it until fuel ran out of filter overflow line. Worked perfectly and saved me much hassle. I used a regular tire valve with the rubber removed from the outlet end, which fit well into the flex line, then clamped it and added air with a hand held air pump. THANK YOU THANK YOU whomever posted that. Problem was leaking fuel pump inlet line, so I removed the pump and installed an electric pump.