I've changed everything over to 12V with a one-wire alternator. I have one horn, brand new (when I bought the truck it was basically a basket case). The wiring harness is also brand new; I installed a Painless Brand wiring harness. I have a wire from the horn to the horn relay and did find the wire from the relay that goes to the horn button. But don't know if the horn wire comes in with the turn signal wires or if it goes up the steering column shaft. My Wife's suggestion was to just put a button under the dash; that ain' happenin LOL.

 

If you have the original steering box then the horn wire comes up trough the steering box and steering column. If have other than the original steering box then you are out of luck unless you want to put a slip ring or some other solution in order to use the horn button on the steering wheel.

T900

 

Its the Original Steering Box but where? Is there a hole near the steering box?

 

at the base. You are much better off passing a wire down the column and pulling it up

 

The steering shaft is like a piece of pipe rather than solid and goes completely through the steering box and exits on the lower side of the box. The wire can be fed through the shaft and then to your horn relay. If you are planning to use the original steering box you may want to consider getting it rebuilt. When I open mine up the internal gears were in pretty bad shape so I opted for a Toyota box which also got me power steering.

T900