Are the heads on a Chevy 350 interchangeable from one side to other?

No, the heads on a Chevy 350 are not interchangeable from one side to the other. The heads are designed to be installed on a specific side of the engine, and they are not symmetrical. The exhaust ports on the left head are located in a different position than the exhaust ports on the right head, and the intake ports are also located in different positions. Additionally, the water passages in the heads are not symmetrical, and the heads are not interchangeable without modifying the water passages.