I recently purchased a complete Dura Ace 7400 set (8 speed, downtube shifters so 7402 parts) with the 7400 headset as well. It's the improved one with the silver race and not the gold one prone to bearing brinneling. So far, I haven't noticed any problems in the races. The headset came with the original bearing retainers (7400 was races or loose ball, 7410 is cartridge).
When vintage headsets do have brinneling, it's recommended to replace the retainers with loose balls to give the headset a second life. In order to keep my headset races functional for the longest time, should I put new bearings in the retainers and install, and then in many years when I need a headset servicing replace those retainers with new loose bearings; or should I skip right to packing new loose bearings now and potentially a second time in the distant future? (The retainers will live in my toolbox so I can have it be "original.")
I've heard people recommend rotating your headset races as a potential solution to mitigate bearing brinneling. Is this relevant or helpful in this situation?
The frame is made by Stowe in the late 80s. While not very historically significant, it's a vintage piece I want to preserve and keep in good condition. I will probably not ride it in regular rain or any races. I'm a pretty gentle rider and weigh 145 pounds.