Intermediate gear spindle orientation

http://www.oldbritts.com/1973_g1.html

#25, the spindle for the intermediate gear (sprocket) , when I took my
engine apart, the hole in the surface of the spindle was
directly down, the slot in the spindle face horizontal.
Is this correct? Old Brits AN diagram seems to show the
slot vertical which would place the oil hole horizontal.

Which is correct?

Your spindle is correct.

Huzzah! ;-)