When confronted with a headset that is brinelled, and you don't have the option of replacing the cups, mark the lower cup and the crown race with a sharpie so you know the "straight ahead" position, then pop them out. Re-install the lower cup offset 90 degrees to the right, and the crown race 90 degrees to the left.
Now you've moved the two worn areas 180 degrees apart, and put fresh bearing surface in the wear position.
Now repack using some serious grease with an "EP" rating. I like Wurth CV joint grease. Molybdenum disulfide, black, very messy. And of course use loose balls in the lower race. Adjust carefully - not too tight, as discussed above! And it's good for another 20 years.
Mark Petry
Bainbridge Island, WA