As somebody who owned a car alarm shop for 15 years, I cannot TELL you the number of times I saw this kind of stuff! It makes me so mad. These old cars simply do not get any easier to install on- try putting a remote start on a 2010 Impala! The radio should never be grounded to anything other than a clean chassis ground. What's incredibly stupid is that there is a very good ground available on the car, right where the radio is. It's a hole that is actually used to ground the harness for any car with a console via a #12 or 1/4 inch bolt I think- and this location works perfectly. The 12v wires (red/yellow) should go directly to the accessory male connectors on the fusebox, via a fully insulated female connector only. Do NOT chop the factory harness! Install your radio the exact same way the factory did the accessories (with female connectors). There is a constant 12v for the radio memory, and a 12v switched that actually powers the amp and tuner when it's on. Most every 67 harness I've seen has a wire available in the factory dash harness that is yellow I think- this is a great 12v ignition wire that will easily work for this purpose. This car stereo installer was probably just a high school kid that literally walked into the shop and lied about his ability. Undo everything he did, repair any scotchlocks or cut wires, and do it yourself! If I had a dollar for every young guy that walked into my shop and said "I'm a great installer", well...................