Erotomechanics VIII, work 423 (1979) by HR Giger references illustration for The Royal International Horse Show (for 19th July 1978 in The Radio Times) by Richard Draper?

leading from

H R Giger's Art
and
Radio Times
and
HR Giger's Erotomechanics VIII (work-423) (1979)

a) Erotomechanics VIII, work 423 (1979) by HR Giger

Erotomechanics VIII, work 423 (1979) by HR Giger

b) Illustration showing "A double obstacle for The Royal International Horse Show course" (for 19th July 1978 in The Radio Times) by Richard Draper.

Perhaps the idea of a double obstacle in terms of his painting made him think about double penetration.

Illustration for The Royal International Horse Show
(for 19th July 1978 in The Radio Times) by Richard Draper

c) The 12 feet arrow sign becomes the distance between te hips and the suspender belt going across, while somehow the horse and rider are merged into the image

d) The horse rider's head becomes a hip bone, his arm becomes a part of the upper leg while horse reign becomes biomechanical suspenders

e) The arrow indicating 25 feet becomes a suspender while the white slanting fence support becomes the pipe entering the vagina

f) Complete page from The Radio Times

 (Image source Graeme Wood @woodg31 on Twitter)