mike ring said

I'm glad I didn't ask for advice - I'd be thoroughly confused.

I'm saying nothing...

I just went to B&Q on wrinklies day and got a nice one with screw in
canister and spark ignition.

I went into B&Q on the way home today. Start at £10 and go up from
there.

The advice here is all good - just a pity most of it doesn't really
apply to my particular question and situation. I looked up the price of
one of the suggested items and it was £59.99 - for that money I might
just as well get a plumber in!

But that is Usenet for you - not complaining, the jems make it all
worthwhile. :-)

--
God Himself, sir, does not propose to judge a man until his life
is over. Why should you and I? - Samuel Johnson -