Thank you Thomas, Jim, for your comments.
The car was built (rebuilt) in the mid-90s by a man with lots of skills but an aversion to buying parts or doing things the conventional way.
He also built a Hebmuller replica, all in metal, from a picture he had on a t-shirt:
The front and rear bumpers are the original metal ones, smoothed and filled and reshaped to how you see them. I have no idea what the front spoiler is, and haven't seen another one in this country, or online, so far as I remember.
The camera always flatters my 914, and what you can't see is the floorpan, which is strong and flex-free, but not as it left the factory (more of a tribute in metal to the art of the patchwork quilt).
But he also spent ages modifying a type4 muffler to have a twin-centre exit that looked like a pig-snout that you can just about see in this picture:
That exhaust pretty-much disolved into red dust soon after I got the car, and I replaced it (eventually) with a 4-1 header and no longer run a rear valence.