I am also an old well driller and I would not have used PB Blaster in the well. But glad you got it out. You can use a little Dawn dish washing soap to help break it down and clean it up. Not too much or it will suds up the water. Probably not going to taste very good for a while.
I forgot to answer your other question with regard to how deep the pump was. It was 31 and 1/2 ft from the bottom side of the pump to the point at which the pump connected to the pitless adapter.
I am also an old well driller and I would not have used PB Blaster in the well. But glad you got it out. You can use a little Dawn dish washing soap to help break it down and clean it up. Not too much or it will suds up the water. Probably not going to taste very good for a while.