How are cylinders numbered small block Chevy?

Small block Chevy cylinders are numbered sequentially from the front of the engine (the timing cover side) to the rear, starting with number 1 on the passenger side. Then they proceed in a V configuration, alternating sides:

1-Passenger side, front

2-Driver side, front

3-Passenger side, middle

4-Driver side, middle

5-Passenger side, rear

6-Driver side, rear

7-Passenger side, rear

8-Driver side, rear

You can remember this easily by visualizing the engine's "V" shape and counting from the front.