When the key is in the on position (RUN) you should have battery voltage at the blue resistor wire. If not it is the wiring, bulkhead connector or at the molex connector. Turn the ign sw on check the DARK BLUE White trace wires on one sides. If you don't power the on both side of the molex connector, no need to go any further. Back to the ing sw. If it's on one side it's the Molex.
Here again with the ing sw on.
If you have power at the molex move onto the engine compartment connector 23 DBL white tracer. If you don't have it there it's in between there and the molex.
If you have power in the engine compartment connector 23 and not at the resistor connection. It's the connector or the wire.
If you have power at the feed or the resistor and not on the other side ( load side) it's the resistor.
There will be reduced voltage on the other side of the resistor (Load Side), that's what it dose.
The test light might not show it has power because it's lower power and completing the circuit. You might see a very dim light. Unplug the load side of the resistor wire is the best way.
If there is reduced power (9v all depend on the the battery state of charge) to the coil, It might be the coil.
The bulkhead connectors are known to be a problem.