Sorry i think you are misunderstanding me but i have no horns at all is what im saying nothing thus i dont even know what is in the steering wheel etc if the contacts are there or anything there are no horns thus i need to find out what i need to do to install them..The 70 Camaro share the same Wiring as the 1st Gen. You can bench test the horns by running a jumper from the Positive Terminal of the Battery to the Green Terminal on the Horns. If the horns work it could possible be the Horn Relay which when grounding the BLACK Wires from the horn Relay will either sound the Horn or the Key Buzzer. If this fails it's a Defective Horn Relay. If the Horn Relay test works it's probably the Horn Ground Contact Circuit in the Steering Wheel in which case you may have to remove the Steering Wheel and repair the Carbon Stick to Ring assembly if the Pad Ground look good.
If you using an Aftermarket Steering Wheel it could complicate matters.