Re:
Thanks for your help guys.
Not tried a knife, but given the shoulder for the crown race on the fork a quick rub with some fine emery cloth. The surface is sound. The internal of the head tube hasn't been touched by shot blasting, the surface is the same as it was believe it or not, they did a really good job of protecting all the open parts of the frame.
Will take the bike (currently bits of bike) to LBS next week and will see what they can do.
Will let you know how things go.