Key in photo fit these JD models. Part number is L22964. IIRC one pushed key in to turn on ignition and pulled out to stop ignition. These early models also use elect fuses that resembled fuses used in VW Bugs
4107 - 3120 Tractor - 12May11 ( FR DE IT ES SV )
4114 - 820 Utility Tractor (North American Version) - 16May11
4152 - 1020, 1120 Tractors - 12May11 ( FR DE IT ES SV )
4163 - 820, 920 Tractors - 12May11 ( FR DE IT ES SV )
4164 - 2020, 2120 Tractors (European Edition) - 12May11 ( FR DE IT ES SV )