41 Logics:

Led Bit    Led
0          Off
1          On

41 Out   C64 In
DLo   -> DHi
DHi   -> DLo
CLo   -> CHi
CHi   -> CLo

41 In   C64 Out

DLo   <- DLo
DHi   <- DHi
CLo   <- CLo
CHi   <- CHi


HD Logics:

Led Bit    Led
0          On
1          Off

HD Out   C64 In

DLo   -> DHi
DHi   -> DLo
CLo   -> CHi
CHi   -> CLo

HD In   C64 Out

DLo   <- DLo
DHi   <- DHi
CLo   <- CLo
CHi   <- DHi