headlight brackets loose on forks ?

I am installing the chrome headlight brackets on my 71 commando and they are a little loose ,am I missing something,thanks,Paul

There should be six O-rings (part 99-0502), one above, and two below the brackets on each side, I'm guessing you haven't got the correct amount of O-rings?

Apparently the replacement O-rings now available from Andover Norton are listed as part = 990522.

Those O-rings being the same part as the carb flange O-rings. And also available as Amal part number 622/101.