Here is a goal: To put a hole in the bottle cap pendant to thread a chain or a string through.

How would you accomplish this goal?

Available choices:
a). Use a 1.8 mm punch pliers to punch a hole on one side and repeat on the opposite side, so you have two holes lining up straight in the middle of the cap..
b). Use a 10 mm punch pliers to punch a hole on one side and repeat on the opposite side, so you have two holes lining up straight in the middle of the cap..
a).