I just had my cluster out to replace my Speedo/odometer. I installed LED lights too ? top round thing is a blank for a clock. There is a ‘brake’ red light and a seatbelts green light. My 68 C code has nothing wired to the seatbelts light. It never did either.
I am not sure if red brake light comes on only when your fluid is low or if it’s supposed to come on via the emergency brake pulled. When I pull my hand brake light does not go on abs my wiring is in really great shape.
Assuming the 68 is wired like the 67 the Brake Warning Light is connected to the switch on the top of the distribution block underneath the master cylinder. It comes on if you lose pressure in either the front or rear brake hydraulic circuit.
So if your brakes are good, you'll probably never see the light come on except maybe when you're bleeding them and if the light ever did come on while you were driving you've probably already figured out that you're missing half of your brakes.
I really like the look of those LED lights. You can actually see the gauges at night!