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.