Main switch and ignition switch

On my wiring diagram for an 81 model it is showing a "Main Switch" and an Ignition switch.. can anyone tell me where to find this main switch" or is it the fuse block ..
Also does the seat lock have to be in a particular position to fire the bike? Thanks in advance.

The main switch is located behind the left side panel

The main switch as mentioned above doubles as the seat lock as well however it is a multi position switch and if not turned to the correct position will not let the bike run this is a legend imprinted in the face of the side cover where the key goes through.

run - full ign and functions
off - no power to bike (early anti theft)
park - power to taillight only bike will not run
spring loaded position - open seat lock

hope this helps

Thanks folks, will give it another try today, thanks for the helping hand..

Still a work in progress .. waiting for the 6 into 6 exhaust system.