Successfully, I think. Saw the last spots twelve days ago, but treated a few days more to be sure (there were several days I didn't get a good look at the fish to be certain; the plastic sides are dim and I had to drape a black cloth behind the tub to get enough contrast). Then spent three days doing small water changes to remove the salt and gradually lowering the temperature, held it at norm temp (78°) a full day extra to keep observing. On the second-to-last day the fish were no longer hiding so much and began to take offered food- garlic-soaked pea bits. They were immediately anxious to escape into the main tank once I started floating in a baggie, so the picture is blurry.
I didn't type out the daily notes on ich treatment this time, but here it is for the record: