On Wed, 16 Mar 2016 13:00:19 -0700, DaveC wrote:

Turns out to get the caps out of circuit requires a 6mm ring spanner
which I shall have to procure from a local emporium tomorrow when they
re-
open. Fortunately I already have a 13mm one for the other ends.

Try 1/4€�. Thats 6.35mm. Might work...

I simply don't have anything that small (apart from sockets which are no
good in this case) in either metric or imperial, I'm afraid. It won't
kill me to buy one the correct size tomorrow.