Radio/Antenna wires?

For Power, there should be a junction coming out of the wiring harness somewhere between the fuse block and the radio. It is a black wire with a molded plastic/rubber "Y" with two or three female jacks. It should have 12 volts when the key is in Run or Accy. You can tap off this for your radio power, but most modern radios also require full time battery power and dash light power. Use your meter and find these as well. a lot of good electrical stuff here:

http://www.geocities.com/midlife66/wiring/wiring.html

and here:

http://www.hammar.dyndns.org/~djhamma/wiring.htm

The antenna is a one piece unit with cable attached and runs from the front fender though a hole near the glove box into the radio. Of course you wont have this if your car didn't come with a radio.
 
I can't seem to find this power cable with the Y. Ugg. I located a green wire that wasn't connected and a black wire with a female end. The male end that connected to who knows was connected but cut. Does anyone have photos of this molded plastic/rubber "Y"? I'm wonder if the previous owner cut the Y connector off?

UPDATE: I THINK I KNOW WHY I CAN'T LOCATE THE Y CABLE! MY WIRING HARNESS IS FROM A 64 1/2 MUSTANG. AT LEAST THAT'S WHAT I CAN FIGURE BY LOOKING AT THE WIRING DIAGRAMS POSTED ABOVE.

IT APPEARS THAT ONLY ONE WIRE, A BLACK ONE, POWERS THE RADIO.
 
In order to install a radio the very minimum you need is a test light. (A multimeter would be better). Use this to see if the black wire is Accesory power (12 volts when the key is in Accy or On)

Unless you are trying to restore the vehicle to 100%, simply use crimps and or solder for the connections and tape (or heatshrink) to insulate. Follow the instructions in the installation manual for the radio you bought and it should be fairly simple.

If you have not bought one already, I recommend a radio that fits the special size Mustang opening. (unless the dash has been hacked already) If a CD player is a must, A trunk mounted system is an option, or a custom built console to house a regular din size just under the dash.

The Antenna wire is a single coax cable and shouldn't be "connected" to anything but the antenna and it plugs into the Radio. It may be "grouped or bundled" with those wires to the courtesy lamp.

Good Luck and have fun. The tunes will sound better knowing you installed it yourself.