You are right, of course, Ian. It was a long time ago and my memory is not always at its best when thinking of bikes I now no longer own. I had the B33's head off (for valves) and so I made the mistake of thinking there was a head gasket in the process.
No need to apologise...I frequently can't remember what I did yesterday, or what I have to do tomorrow....As for today, getting the day of the week right and remembering where I've put everything is the challenge...:laughing: ....Ian