I have a 1970 Duster manual MC with front disc.
Looking at your second picture, the top port is for the MC-- port closest to fire wall, front brakes.
The next two ports are across from each other and they go to each side of your front brakes. Front port to drivers side.
The next two ports are across from each other. The front port is for the MC--front port, rear brakes.
The other port goes to rear axle. There it splits and goes to eash side.
The bottom is where the proportioning valve goes.