All individual engine components are identified by a casting number, they are not sold and bought by part numbers.
This engine block number can be found to the back on the left hand side. The numbers are raised castings on the block behind the starter. All engines have different locations, this is one illustration only.
Cylinder head numbers on this model are located to the front of the head on the top side.
If you need help locating the casting numbers on you John Deere engines and/or parts, please feel free to call Gary at (712) 260-9834.