Cam Timing
As said, either is correct, in one position cyl#1 is firing, in the other position cyl#6 is firing. - both pistons are at TDC at the same time.
That's why you can set timing on an engine with either #1, or #6 plug wire.
( V-8 and most 6 cylinder engines )
Both will be correct . ( If crank is indexed correctly).