My Friend, Topper Kang has the rear setup you describe, and is detailed in the Jensen Manual. His is a full race TC, and its a legal mod for his vintage race group. However, it has no emergency brake and the parts are hard to source. Two little tiny slave cylinders per drum, and they can overheat easily, so its recommended to vent by drilling the backing plates, which is kind of scary. And you have to source race pad material and get the shoes specially 'retread' by a known brake vender. Not cheap. I have a spare setup, from a Metropolitian Nash (same setup as the Herald) that Topper ran across in a pick a part and he picked up for my S1 racer I intend to build, if I ever get around to it. I believe the backing plates have to be offset to suit the Europa axle setup also, which is tricky. I think they were 1 3/4 wide shoes though. Anyways, they are difficult to setup, hard to source parts, and with no emergency brake makes them a poor choice for a street car.
Jerry Rude
4005R