On 15/12/2016 14:44, Dave Plowman (News) wrote:

Get a cheap one and grind it down?

+1
I did this to a ring spanner MANY years ago to reach something (probably
a cylinder head nut) on a BSA C15 or a Triumph T100SS ... I presume
there was a special service tool but a quick grind got around the
problem. Just keep quenching it so it doesn't overheat and spoil the temper.