One more thing to think about. On my 1974 Raleigh Pro track fork, while I could see 'N' speckles, there were actually '3N' speckles total !!!
When I attacked the tangs with a wire brush, these other speckles (which previously had been tiny lumps that hadn't breached yet) opened up and became visible. So you could make the problem look worse if you try drastic measures !!
- Don Gillies
San Diego, CA, USA