Converting a monitor from 625 to 405

[Nick]

...must get around to mounting some in boxes for this sort of job...

Some years ago I picked up a s/h ISB-060W medical isolation transformer for about 40 quid - I reckoned that by the time I'd spent several hours messing around and getting the bits I didn't have, it was a good deal - they crop up on eBay in the UK from time to time.

There's a few around at the moment, but not in the UK - they are worth waiting for... Note that you need the "W" version as that has the IEC 60320 type "F" outlets that you need for the UK.