To sum this up, you can NOT ASSUME ANYTHING.
Might be the block. Might be rod(s)
Might be piston(s)
Might be CRANK
The normal thing, "generally" for deck checking is to check a piston, or all of them, and a rod, or all of them, and pick a pair, and put that one setup in all 4 corners of the block and measure deck height from there