Another solution, and my last resort in the very few circumstances where euco either doesn’t work or (more likely) when the surface area is so large that euco isn’t economical, is metho – metholated spirits to those not from ‘Straya. (Tom do they say metho in New Zilland? You can add that to the blog post on Kiwi terms). If you can’t get it off with euco or metho, stop bothering.