Went for a long ride today in my '55 TBird.  The cars runs great with no issues.  When I pulled into the garage I heard a knocking noise coming from under the hood at idle.  I recently changed the heads and rockers, so I thought one of my rockers had loosened up. The knock sounded like it was coming from the fuel pump.  I used a long screw driver and the noise was not coming from the valve train like I suspected.  I could definitely hear it coming from the fuel pump itself.  I shut off the engine to let it cool down and the noise quit.  The pump is an old 292 dual action pump with the vacuum lines plugged. Anyone ever had a fuel pump do this?  I don't need the vacuum. Will a standard FE pump work in my 292?