Just thought i would share my experience with the 356 brakes. I was fortunate to have early 356 A brakes, later 356 A brakes and 356 B brakes at hand when i wanted to fit CB dropped Spindles. I found on all bar the early 356 A brakes had a clearence issues with the link pin carriers (the Bottom link pin). The early 356 A brakes backing plate was flatter than the rest with a reinforced plate on the outside where the bolts attach the backing plate to the spindle. I had to grind down a 2 mm corner on the spindle mating face to get a flush fit, and had no clearence issues at all. The early 356 A brakes are distiguishable in that they only have 1 bleed nipple on the brass junction union between both cylinders. ie, the bleed nipples are not directly into the cylinders. I did not want to grind part of the lower link pin away, or modify the rear backing plate, as many do, and found that the only way to go was to use the early 356 A brakes. Now having said that, the early A brakes are fairly rare, and the cylinders for them even rarer, howevere, you could fit the later cylinders by cutting out the notch in the backing plate to clear both bleed nipples. I also noted that the drums & backing plates on the 356 A and B brakes are Not interchangable, the B brakes being a bigger diameter. If any one is intrested, i have a full set of later front 356 A Brakes for sale, completely rebuilt with new parts, and the cylinders have a stainless steel sleve in them. I ran them for about about 100 miles, before deciding to drop the car on dropped spindles.