according to the febi bilstein partsfinder,
there are 10 mm and 12 mm thick breakdiscs (https://partsfinder.bilsteingroup.com/de/search/make/Volkswagen/model/Golf%202%20(1G)%201986%20-%201992/vehicle/1.3%20-%2040%20kW%20%7C%2054%20hp/article-group/Bremsanlage/sub-group/Scheibenbremse?q=bremsscheiben&sortby=rel&t=a&sortdir=asc&f=31) (i couldn't get it up in english),
for the 55hp machine.
but the wear off maximum is always 2 mm. why ?
cause of the burr forming on the outside ?
would one need different calipers for 10 and 12 mm brake discs ?
for 75hp machines they only recommend 10 mm discs. why ?
thicker discs for more powerful machines, would have been my guess.