Stronglight A9 is great, but I understand if you don't like the Italo/Franco mix on such an Italian frame. You can maybe go with a Miche Primato (Italian) needle bearing headset, if you want similar performance.......and maybe durability (Can't totally vouch for Miche as much as Stronglight in that category).
I agree about grinding the eyelets off to avoid any heat damage to the frame and the brazing at the DOs. I assume that the DOs are painted anyway and that you will not see the work, but as long as you take your time, you might be able to do it clean enough to make it almost undetectabel.
Chombi