Leslie: Numbering 5p DIN shows 1,4,2,5 and 3 from left
to right. I think yellow and orange is used for output signal but what
about the red and blue? If yellow/orange is correct where do I connect
them on the 5p DIN connector?
Don't you just love how people cut off the DINs?
The
black 6-pin connector at the other end of the cable is P9 and numbering starts
from 1 on the left in your 3rd picture, so that should be enough with
this excerpt from the service manual
(note that the pins aren't drawn in numerical order in the schematic - you seem to be right with YE/OR being left front / right front)