Unfortunately it isn't a wind up. I had set the timing correct and tensioned it etc.
This has turned into a nightmare.
Use the pictures as a guide. They are as it should be (unless I've been drinking!!)
But also make sure the crank is locked through the flywheel with a locking pin or 6mm drill bit. Don't be tempted to use the 2 dots on the lower pulley, they are not always that accurate.