Can I use a mechanical fuel pump from a 425 on a 430? I want to eliminate the return line port on the fuel pump that is on the 430 pump as it is a potential leak point. The 425 pump doesn't have that 3rd port
No, the 425 is a Nailhead engine, a different design. All you need to do is block off the return line if you don't want to use it. There isn't that much pressure there.