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ray_mcavoy · 10-01-2013, 10:46 PM

Hi Jason,

Your existing warning light type cab harness should have that brown/white wire running from the ignition switch to one of the terminals on the driver side bulkhead connector. At the connector, it will be crimped into the same terminal as the solid brown wire that goes to the "GEN" light.

The re-pinning I mentioned in (5) involves separating those two wires by cutting the brown wire with the white stripe close to the bulkhead connector. Leave the solid brown wire attached to the terminal and leave the terminal in it's current slot in the connector housing.

Obtain some male and female Packard 56 series terminals ... they're available from NAPA and other places. Crimp one of those terminals onto the cut end of the brown/white wire. If I remember correctly, the cab side takes the female terminals.

The warning light type cab harness should also have one empty slot in the driver side bulkhead connector that's not currently occupied by a wire/terminal. Snap the newly crimped terminal on the brown/white wire into that slot.

That completes the modification on the cab harness. The solid brown wire will become one leg of the ammeter wiring. For reference, the factory used a black wire with a white stripe for this part of the circuit but it follows the same routing.

Now you need to do some re-pinning on the headlight/alternator harness that plugs into the under-hood side of the driver side bulkhead connector. That involves:

(1) Locate the brown wire that comes from the #4 terminal on the voltage regulator and remove it terminal and all from the bulkhead connector. The male Packard 56 terminals used here can be removed from the housing by squeezing them edge wise and carefully pulling on the wire. Re-form the terminal afterwards by spreading it apart a little with a narrow screwdriver in the terminal's center slot.

(2) The under-hood side of the driver side bulkhead connector will also have a single unused slot that corresponded to the unused slot on the cab harness. Take that brown wire/terminal removed from (1) and insert it into that previously unused slot.

(3) Crimp a male 56 series terminal onto a section of 20 gauge wire (factory used black w/white stripe) and insert it into the slot that was vacated by the brown wire removal in (1).

(4) Connect the other end of the 20ga wire added in (3) to the buss bar / junction on the horn relay. The buss bar / junction is the part with the 2 screw terminals. Hook it to either screw. Adding a 4A inline fuse to this wire near the horn relay end is highly recommended.

That'll complete the modification to the headlight/alternator harness.

One final note, you shouldn't have to re-pin anything on the cluster connector of the cab harness.

10-01-2013, 10:46 PM	#5
ray_mcavoy Registered User Join Date: Nov 2009 Location: Sherman, ME Posts: 2,358	Re: Warning lights to gauges Hi Jason, Your existing warning light type cab harness should have that brown/white wire running from the ignition switch to one of the terminals on the driver side bulkhead connector. At the connector, it will be crimped into the same terminal as the solid brown wire that goes to the "GEN" light. The re-pinning I mentioned in (5) involves separating those two wires by cutting the brown wire with the white stripe close to the bulkhead connector. Leave the solid brown wire attached to the terminal and leave the terminal in it's current slot in the connector housing. Obtain some male and female Packard 56 series terminals ... they're available from NAPA and other places. Crimp one of those terminals onto the cut end of the brown/white wire. If I remember correctly, the cab side takes the female terminals. The warning light type cab harness should also have one empty slot in the driver side bulkhead connector that's not currently occupied by a wire/terminal. Snap the newly crimped terminal on the brown/white wire into that slot. That completes the modification on the cab harness. The solid brown wire will become one leg of the ammeter wiring. For reference, the factory used a black wire with a white stripe for this part of the circuit but it follows the same routing. Now you need to do some re-pinning on the headlight/alternator harness that plugs into the under-hood side of the driver side bulkhead connector. That involves: (1) Locate the brown wire that comes from the #4 terminal on the voltage regulator and remove it terminal and all from the bulkhead connector. The male Packard 56 terminals used here can be removed from the housing by squeezing them edge wise and carefully pulling on the wire. Re-form the terminal afterwards by spreading it apart a little with a narrow screwdriver in the terminal's center slot. (2) The under-hood side of the driver side bulkhead connector will also have a single unused slot that corresponded to the unused slot on the cab harness. Take that brown wire/terminal removed from (1) and insert it into that previously unused slot. (3) Crimp a male 56 series terminal onto a section of 20 gauge wire (factory used black w/white stripe) and insert it into the slot that was vacated by the brown wire removal in (1). (4) Connect the other end of the 20ga wire added in (3) to the buss bar / junction on the horn relay. The buss bar / junction is the part with the 2 screw terminals. Hook it to either screw. Adding a 4A inline fuse to this wire near the horn relay end is highly recommended. That'll complete the modification to the headlight/alternator harness. One final note, you shouldn't have to re-pin anything on the cluster connector of the cab harness.