The Brown wire is the + 12 volts (hot wire) for your parking/running lights. Double check that you are seeing a solid brown wire. There is no solid Orange wire, but there is an orange wire in combination with another color. What is the other color on the orange wire? The red/light green wire, is one of the resistance wires, and connects in multiple places. It starts at the ignition switch, and goes through the firewall plug to the positive side of the ignition coil, and also goes to the "I" terminal on the solenoid. "I" will have power in both the run position, and the start position, for different reasons, when it is working properly. There are TWO SEPARATE CONTACTS THAT CLOSE in the solenoid, when cranking the keyswitch/starter in the "Start" position: 1. The MAIN contact closes (the large terminals on the solenoid) which connect the battery's positive voltage to the starter. 2. The smaller "coil boost" contact closes in the solenoid, connecting the battery positive to the "I" terminal on the solenoid, which leads to the coil's primary, and is for applying extra power to the coil during starting. The "s" terminal on the solenoid should only have power when the key is in the start position.
Hi NorCalMaverick, from your photos, it looks like alot of that wiring is not the original factory wiring, so that makes it more difficult to just say what color wire goes where. It would work better if you saw the schematic for your year car. Here is a link: http://1bad6t.com/Maverick/repair/pdf/74maverickwiring.pdf
I see the starter relay and the red/blue, red/green, and a yellow fusible link but the brown is for the running lights
