Hi All, sorry to be slow in replying, but have been entertaining at home (I notice this could have more than one meaning, but I'll leave as is.)
Let me first clear something up. The title / question of my post, referred to persisting with the head gasket that was in situ, not with the whole project - I may be an idiot, but even I'm not that dumb!
cjandme - compared to my old Commando, which had some performance mods, this bike really does shift. The carbs need rejetting, so I'm not sure that I'm getting all the performance that should be there, but even so, I've had to invest in a humped solo seat so that I'm not constantly having to strain to stop myself sliding backwards when accelerating.
Matchless - I think you make a good point with the Maney liners being a smidgen proud and makes me wonder if I should use slightly thicker wire than the 0.005" suggested by Jim Schmidt, should I need to fit a copper gasket. The flame ring gasket I used was an 850 one and was assured by Les Emery that it was normal to use said gasket. Visually, it seemed to fit ok.
Hobot - In agreement with the torque wrench thing and, if I feel the pressure required is too low, I nudge it on a bit. Difficult though if it is the fastener itself that's giving the extra resistance.
Thanks for everyone elses contributions. I'm as sure as I can be that the rocker covers are not leaking. I may buy a spring balance and will definitely check the dimensions of the copper gasket I have already.
Cheers, Bob