Cleaning pistons

When I was still in high school, I worked for a local mom and pop machine shop that was opened in 1957. The owner opened it upon his return from the Navy. He had a 55 gallon barrel with 35 gallons of carbon-tetra-chloride in it. That stuff would clean the nastiest carburetor you ever saw in an hour. It was some bad stuff.
he could sell that 35 gallons today and retire on it. $500/liter nowadays.