The longboard
is designed for
the C64 + 1541 / 1541Late
The shortboard
is designed for
the C64C + 1541C / 1541-II
The innards of C64
/ C64C
and 1541
/ 1541C
are often mixed together, and you must check their
cases to be sure which boards they have.
Based On Sven Petersen
C64 Kernal Adaptor Switch Shortboard
Old Version DiscoHR
It is possible to reused the original LED / Cable assembly.