All done with the cleaning, and now I just need to reseason. The last bit of carbon on the inside wall was the most stubborn. At the final stage, I "spot" cleaned with oven cleaner, still using the bag. This was much less involved than spraying the entire piece, and I could do it in my kitchen sink. A small, stainless steel brush that I got at a hardware store for under $2 came in handy, too.
If I had a basement, attic, kitchen or garage full of old cast iron in need of cleaning, I would definitely go with a lye bath instead of the oven cleaner in a bag method. For my one piece that had so much build up created over decades, the method did work fine in the end.
I am looking forward to a steak cooked in this skillet later on this week.
