Will an Italian threadded headset fit on an English frame and forks? I'm currently building a roadbike with slightly dated components and was wondering if a Campagnolo headset will fit on my frame? It's a Holdsworth, so the fork threads are English spec.

I know what size the headset has to be, but I'm concerned about the Italian threading as according to Sheldon Brown:

"Obsolete. Threads are cut at 55 degrees, but ISO or J.I.S. headsets can be used."

And I was wondering how this degree cut in the threads would affect fitting of the headset?
The fork threads are the only threads to worry about in this case. Assuming an English threaded fork, a Campy headset which is recent manufacture should be no problem.

If it is Italian threaded, it should specify. The major worry for current bike threading issues have to do with the Bottom Bracket thread.