[Bored&Stroked]

I'm with David, it is really rare to see a worn fuel-pump pushrod as the cause of a fuel delivery system issue. My bet is that if it was running with the current setup, the pushrod is not your problem. It can easily be an issue with the pump itself or the short flexible/braided line between the hard line and the fuel pump (sucking air) or another line/tank issue.

Give us some history on the engine and the problem you're trying to fix.