Yes a mohair hood. I've checked the frame assembly with pics of fthe swivel pivot website and that looks ok. The hood has always been a bit tight but its not been on all winter so not kept to shape. I guess washing it off the car was a bad idea. Its also cold out in the garage so have warmed it up.
The hood is now on as the back end was clipped down overnight but disconnected from the windscreen. Seems that its settled down width wise. I've heated it up with a hairdrier and that has helped easing it back onto the windscreen.
I like the idea of hot water bottles but will go a stage further and put an electric blanket over the hood to warm it up evenly (yes really!) and help it to settle down.