I am going to assume you must be trying to remove the pump by removing the two bolts with round heads on the outside of the engine. DO NOT DO THAT!
The bolt that holds the pump in is on the inside of the engine. It takes a 1/2" wrench, and has a lock nut on it tightened against the block to prevent it from loosening. The lock nut takes a 9/16" wrench.
Sorry, I could not easily come up with a picture.
I am assuming you are asking about a 1937-62 engine.


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