Pulled the forks out today, and wondering what model the headset maybe. Forgot to take a photo of headset parts off the bike though.
I obviously don't have the lock nut to give a clue as it's been replaced by an OMAS one and the huge spacer. I thought it was going to be a Campagnolo Gran Sport, due to the top cup only having two flats. But the cups are unmarked - no engraving on top, outside and the NOS GS one I have has the 'Patent Campagnolo Italy' markings which I thought was standard on GS models? The very early Campagnolo headsets, from what I can gather don't have any engraving either, but have flats all round the top cup. There is engraving inside the cups 'Made in Italy' and '1" x 24 tpi BRITISH' and bearing cages with 'Brev Inter Campagnolo'. Would need to take apart again to confirm.
On the forks being non-original, the steerer has 9/11/91 in marker pen on it, and engraved HEATH. Thinking this might be Haywards Heath Cycles, Sussex as the bikes previous owner was near Crawley so not far from there. Anyone know anything about them, did they make frames etc or do frame repairs? I could always ask them directly.
Thanks again, Daniel