Folks:
Here is the link to the ERA website that shows the "inboard" brake rear:
http://www.erareplicas.com/427/rsusp.htm
And here is the link to the "outboard" brake rear:
http://www.erareplicas.com/427/frsusp.htm
The outboard brakes only cost a few "pintos" more. (Peter will explain the pinto concept).
Jim Holden
PS: The brakes on ACs were inboard, but in racing tend to get covered in
oil and difficult to change pads, etc. in the heat of an event, even though there is less "unsprung" weight.