I've got an Italian frame that previously had a Japanese headset that I assume had a very short stack height (I never saw it, I got the frame/fork unattached).
I put on a NR headset, but once I had it all together, I noticed the steerer tube was flush with the upper head cup. There were no threads for me to attach the lock ring.
I think old school 105 and 600 headset stack heights are a lot shorter than same-era Italian headsets. So.. any recommendations?