[6pack] A type OD top cover switch question

[Bud Rolofson]

List,

If an A type OD has three switches on the top cover does that means it  
has a seat belt interlock? And if it only has two switches on the top  
cover does that mean it only has an OD and reverse switch without a  
seat belt interlock? What year did the seat belt interlock switches  
appear?

Thanks
Bud Rolofson

71TR6 CC57365 (Good 6)
66TR4A CTC57529 (The Project)
71F-250 Camper Special (Triumph Support Vehicle)
Z-50A Hardly Davidson 1977 Honda Mini-Trail Bike (Triumph Pit Bike)
levilevi at comcast.net