Hello gang, was wondering if anyone would know the easiest way to hook up my new stereo in the 75? I have three wires a red ( switched I think),  yellow ( Constant),  black ( Ground). Now I don't really have a clue where to hook them up to. They are wired in and I have no power, so I goofed somehow. Any help would be appreciated.

New stereo have any installation destructions?

It states on the instrection sheet paper as follows:

I am assuming you had the speakers properly connected?  If you made good connections as you described, the only explanation is a bad unit. 

Larry

I remember having a hard time finding a good ground.  I think I ended up using the same one as the cluster (which in my 74; is located at the bottom left when looking at the cluster; there`s a screw holding the transmission plate).

I don`t know if it`s the same on 75, but I also remember that my original speakers were connected to an amplifier.  I replaced the speakers and removed the amplifier; as this original amplifier would not work with today`s radio`s.

Do you have a multimeter to verify the connections?

And as a bonus: I think the engine noise could be heard through the radio, so I added noise cancellation thingy connected near the speakers.  It works good on FM, but so-so on AM.

I am having the same problem. If I hook up the red/yellow from the stereo to the 12v positive Yellow battery it works fine but powered al the time, I want it to work only if ignition is on oro acc position and I cannot find that wire. It should go to the red radio wire but cannot find the acc wire to tap into.   And now I cannot get the antenna to go up and down but think if I get the acc wire it will work. Let me know BB78

If I have this right; there is no secondary "power" wire available in our car; which are required for today's radios.  One is to power the radio by itself and the other one is to keep the electronic radio settings and the clock.

To get my secondary power; I tapped into my cigarette lighter; which should be 12 volts.  However, I noticed after a while that this; combined with the Vette clock; it slowly drained my battery all the time.

My remedy to this was to add a power cut-off switch to my battery (quick disconnect they call it sometimes).  No more drained battery; but the downside is that my radio settings (presets and clock) are not kept.  Doesn't bother me enough to find a solution.

I don't have an electric antenna; so I don't have much to say about it.  I would think the power of the antenna is also coming from the same acc. power you have yet to find (again; cigarette lighter worked for me, but it's a very short wire and little space to work with.

Steph.

As someone mentioned earlier, finding a ground is usually key to radio solutions..  With a multimeter, you can find a hot wire on the original radio connection plug(if its still there), otherwise, you will have to tap/splice into a wire somewhere in the cluster,  think i used the voltage meter or amp guage wire on the instrument cluster as a key switch wire, and the ciggy lighter wire as a constant hot.  Then took the ground wire and ran it to the console frame, or the shifter bracket(if its an auto). Good luck!