Yes! Got the jet out. Here's some pics just in case anyone else is having a go... Just like the man says:
Unscrew the screws on the cover (there are actually 8 on mine - five on the bottom and three at the end):
Undo the bracket at the front of the fridge:
Undo the gas pipe:
and the larger nut that retains the jet:
Unscrew the U shaped washer at the other end of the flame tube. Pull the flame towards you:
and the jet virtually drops out:
Its now soaking in carb cleaner - I couldn't get the sealing ring off without mullering it so I hope the carb cleaner wont dissolve it!
Also the housing gasket is just about OK - I took it off very carefully - does anyone know if replacements are available?
Hopefully all this will go back together. I have found one other problem which is that the piezo only sparks intermittently. I went out last night in the dark to check it because I had a suspicion something was up. It tends to work for the first 2 or 3 tries and then sometimes will work every time and others not until its been left a few minutes. Does anyone have any ideas on this please?
Just like to say thanks very much for all the advice last night. Got to get to work now but will try and put it all together this evening and see what happens.
Pete