You want the Beogram output DIN pins 3 and 5 to go to RCA Left and Right respectively. Pin 2 is ground.
But if you are making your own lead and only have a 5 pin DIN socket you will need to removed DIN pins 6 and 7 (they unscrew).
EDIT: Pin numbers looking into a 7-pin DIN socket (or looking at solder side of DIN plug):
I would be tempted to purchase one of these ready made leads from our site sponsor: https://soundsheavenly.com/beogram-record-players/14-2244-beogram-to-non-bo-device-phono-pre-amp-receiver-amplifier-etc-bo-ref-.html#/2-length-1m/60-grounding-internal_ground_link
Location: Warwickshire, UK
My B&O Icons:
