I needed to figure out how the brakes and hangers were going to fit, so I made the cross supports and installed the hangers.  Needed brake shoes, so I ended up making them also.

I then machined the brake cylinders.

Then I had to figure out how I was going to make the brake rigging.  Came up with this...

 The rigging works excellent.  Here it is, all put together and ready for some compressed air.

 Having tested the brakes in real world situations, I can say that these brakes work excellent!