[A26B]

The SS fuel block at the RR corner of the plenum is actually the fuel feed & return block. There is only one fuel feed line for both fuel pumps, as the single fuel filter would confirm.

The feed line goes directly to the fuel pressure regulator, pressure regulated fuel then is piped directly from the regulator to each fuel rail. Finally fuel is returned from both rails by piping to the single return line, which is the one closest to the firewall.

A single gauge would be sufficient and should read regulated fuel pressure. The most ideal location would be on either the L or R pipe between the fuel pressure regulator and the respective fuel rail. The pressure regulated fuel lines are the one nearest the top of the regulator and towards the front of the engine. The pipe could be removed, small hole drilled in the line and an appropriate SS fitting for the sender then welded onto the line over the hole. Reassemble & you're good. Ever decide to remove the sender, just plug the fitting.