That diagram is not even close to what you have.
You do not have the EEC system, you have no EEC Module (aka computer) an no EEC relay.
You have a Fuel Pump relay but it is not wired like that.
You should have the Duraspark II Ignition system and not the EEC TFI system.

As I said above for vapor locking problems get this fuel vapor valve, E0TZ9N176-B .090 Used as a field fix for units experiencing hot fuel problems.

To test the fuel system and pumps you need to jumper the oil pressure switch (photo below) and turn on the key. At that time the selected pump should run all the time.

Yes I would like to have photos of the oil pressure switch (the one below is from an E series), and both fuel relays, the selector valve on the frame, the Inertia switch and the starter solenoid showing the fuel wire. I need most of the photos to show the locations of the items for other posters on the forum.

Here is a wiring diagram of you fuel wiring but the colors may be wrong:


Jumping the oil switch:


Another wiring diagram for the right wire colors:


The starter solenoid (relay):


There starter solenoid wiring:


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