I went with the punch and pin vice, and that worked fine, thanks.
Just curious, do you have transfer punches, or did you just use a standard centre punch?

Good advice. I used a stanley knife blade, and just scraped away the excess. Took a while, but delivered a good result.
That's great. Depending on how material I need to remove, I'll tackle the bulk of it with the files, then use the blade/scraper to finish it off and get nice clean lines. A fresh, sharp blade is best so you get "chatter".