No suffix on the original movement. No mention when ordering that there are variations - just high and low bridge, and pendulum length. Looking at the location of wheels, one cannot take from the old to add to the new to have a second hand.
Allow me say that if the movement came from Butterworth, exchange is no problem. 1980 was a transition year in which the movements were not always marked with current markings. On the Butterworth website, the part number is 451-053 then SK 94cm. It is not common for that unit to require a seconds bit, but obviously they are out there. In the part # the S stands for seconds bit and the K made in Germany [for reasons known only to God].
I might mention on these Hermle grandfather units regarding variations,
the default without letters will be high bridge auto beat.
DB means dead beat or manual beat set [even though both manual and auto beat are dead beat.]
DBL means dead beat low suspension post or bridge
SK means seconds feature.