Thanks both. I ended up going for a combination of hole saw and hacksaw not having tin snips. Had to cut off a bit completely on the right to get it in over the pipes. I can’t say it’s the neatest but just about managed to drill a hole for one of the wings m under the pipe (a very close fit) and them an even closer fit lying on my tummy to screw it in.
The bit I chopped off I have wedged in and screwed in to the gravelboard on the fence. I didn’t get the measurements quite right on the left hand side but it was pretty tricky with the pipes and I certainly wasn’t removing any pipework as I am well aware of where my competence ends. Presumably a lot easier if not retrofitting.
I don’t think I’m winning any marks for presentation here but I think it will do the job.
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