Reverse lamp wiring for a 4 speed 1971 Road runner

[71Beeper]

Similar to Air Grabbers post about the reverse lamp wiring, but my question is for the wiring that goes from the back of the transmission.
I bought the wiring harness for it. Where does the other end get plugged into?
Is there a spot on the bulkhead for it?

 

[bee71]

Same as B body.

 

[72RoadrunnerGTX]

 

[71Beeper]

bee71, here is a pic of my firewall - slightly different than the one you posted.

My car did start out life with an auto transmission - I converted it to a 4 speed setup.
I assume that I may have to drill an additional hole in the firewall for some of the harness to go thru?

Doug - thanks for the schematic. What say you about needing an additional hole in the firewall?

 

[72RoadrunnerGTX]

In ’71? Hole in the firewall? Just for the dash mounted reverse indicator light’s wire and gromet. Connects to the pigtail in the above diagram on the engine compartment side of the firewall. Bee71's pic above shows the reverse indicator light wire grommet location.

 

[T2R9]

When I added mine I just tapped into cavity 7 on the diagram 72RoadrunnerGTX shows on the interior side of the bulkhead connector.

 

[72RoadrunnerGTX]

When I added mine I just tapped into cavity 7 on the diagram 72RoadrunnerGTX shows on the interior side of the bulkhead connector.

I agree, have done the same thing myself several times, there is no technical need to make this indicator light connection in the engine compartment. That’s just how the cars were assembled originally. I certainly wouldn’t be drilling any new unnecessary holes in a freshly painted firewall for that purpose when the circuit is already present on the interior side.

 

[bee71]

If you have changed to a 4 speed there is a switch on the trans for illuminating the reverse light. The wire from the trans feeds through the firewall.

bee71, here is a pic of my firewall - slightly different than the one you posted.Brewer's Performance - Mopar A833 4-Speed Transmission and Component Specialists
View attachment 1440991
My car did start out life with an auto transmission - I converted it to a 4 speed setup.
I assume that I may have to drill an additional hole in the firewall for some of the harness to go thru?

Doug - thanks for the schematic. What say you about needing an additional hole in the firewall?

 

[71Beeper]

That's what I thought as well bee71.
Now to find out where that hole might be located.

 

[bee71]

That's what I thought as well bee71.
Now to find out where that hole might be located.

Refer back to the pic I posted. E and B body firewalls are the same. Look at where the hole is. If you are going to get the wire you want to be pretty close to that location as it feeds around the torque shaft on it's way into the underside of the dash.

 

[Nacho-RT74]

When no hole opened at certain sheetmetal location for any non added accessory from factory normally a dimple can be found on spot.

 

[Nacho-RT74]

Refer back to the pic I posted. E and B body firewalls are the same. Look at where the hole is. If you are going to get the wire you want to be pretty close to that location as it feeds around the torque shaft on it's way into the underside of the dash.

not really. REALLY CLOSE but not exactly the same

 

[71Beeper]

Okay, I was able to get a few pics of the wiring.

I will take T2R9's advice about tapping into the cavity 7 on the diagram 72RoadrunnerGTX shows on the interior side of the bulkhead connector.
That way I do not have to put any more holes in the firewall.

 

[71Beeper]

So I tapped into the wire at cavity 7 - no issues.
Is there a similar way to hook up the factory tach or does the wire have to go to the coil?

 

[QuickBpBp]

So I tapped into the wire at cavity 7 - no issues.
Is there a similar way to hook up the factory tach or does the wire have to go to the coil?

That is a separate harness also..

 

[71Beeper]

Yes, I do realize that.
I was just hoping there was a way to tap into the bulkhead to get the factory tach to work instead of running the trigger wire all the way to the coil from inside the car.
That's all.