DavidL wrote:I think that's correct. I'm almost certain they were made by Midas. I don't think there was a separate seat base, I think it was just padding and upholstery on top of the floor of the car.
That's right, the base padding was stuck to the floor, but there was a separate seat back, consisting of a simple steel frame and a plywood panel. This was hinged from the floor, giving a flat floor when folded forward, and was held upright by a pair of catches. I don't know where the catches came from originally, but it should be possible to adapt a pair of catches from just about any estate car to do the came job.
I will be picking up a Mk3 Coupe with the original rear seats fitted on Wednesday. I will try to take some photos of the seat back and catches and post them up.