1. The horn for the 73' has two wires, the 76' has one wire. What is the best way to resolve this.
This one should be pretty straightforward as far as the column is concerned, but you'll have to get creative under the hood, or dash as well. You need to add a horn relay that your '73 did not have from the factory. But this is a good thing as they should all have come that way.
Not as easy as adding a relay to an existing '73 column, but doable. I'll make it needlessly more confusing by writing it all out!
Make sure that your steering column has a path to electrical ground through the center shaft. If you are using a rag-joint isolator in the lower shaft this means you will have to create a jumper of some kind if none exists now. Electrically connecting the upper and lower shafts together, where the rag-joint itself is isolating it.
Normally the relay would be mounted under the hood, but in your case it might be easier to mount it under the dash. Use a standard 30 or 40 amp rated "Bosch type" relay for it's availability, cost and standardized numbering system.
The Yellow wire in your body side connector has 12v and is hot all the time. It gets it's power from the headlight switch. Cut the Yellow wire on the body side of the column connector and attach it to the #86 terminal on the relay.
Attach the remainder of that Yellow wire from the column connector side to the #85 terminal. This will then run up into the column and ground out to the shaft when the horn button is pressed.
The Blue w/yellow wire gets removed from the column connector and is connected to the #87 terminal on the relay. This runs straight out to the horn and gets 12v when you push the horn button and trigger the relay.
The #30 terminal on the relay needs battery power all the time. You can either splice into a constant hot power feed somewhere, or make a small jumper wire between your relay's #86 and #30 terminals.
2. What is the Auto indicator light? I don't have a wire for that on the 73'.
You would need to tap into one of your other Blue w/red wires under the dash. On your '73 these would be found either at the back of the instrument cluster, or leading into one of your light bar indicators under the control knobs.
Alternately you could find that cavity on the headlight switch connector and add a wire there to attach to the steering column wire.
Using the Blue w/red wire gives it the same function as the other dash lights, so would go on and off, and dim and brighten with the headlight switch.
3. What is the 4 way flasher? I don't have a wire for this on my 73'.
Personally, even though I prefer it on the column, I would not bother with the hazard wiring unless you have to for proper turn signal function. You already have a hazard switch on the dash, so no reason to get too fired up about re-wiring it.
Hopefully someone with more knowledge of this stuff will put their 10 cents worth in. I know there are 33 1/3 ways to wire a relay to have it do the same thing as I suggested wiring it, but another way might be simpler given the existing wiring differences.
And I really don't remember how integrated the hazards are into the turn signals that might effect how you use your old one on the dash or new one on the column.
But you've got some starting points to mess with at least.
And in case you were not aware, you will need to use the steering wheel off of the '76 or the horn won't work. As you found out, the early models had two wires and therefore two contacts under the wheel. The later models only had one, so the two types of wheel are not cross compatible.
Paul
