Found the rear mudguard was lower than normal. When I looked at the mudguard where it fixes to the plastic of the frame and the rubber well nuts had split and the rear mudguard had dropped down. Out of the three only one was holding on. With a search on the net for spares.
I found the rubber well nuts on ebay and have fitted the mudguard back on. It was easier to remove the wires to the back light and the indicator. As I have a alarm then I had to mark the wires with colours with masking tape so that when I reconnected them. The right wires were connected. This took a little longer but the amount of space is very small in the mudguard area. I find when working if it takes a little longer than it is worth to take this route. Short cuts often end up taking longer with me.
I put a little silicon grease on the rubber well nuts and popped them back in the locating holes on the mudguard. The old rubber well nuts came out as they had separated from the nut and the rubber.
I placed a short video on youtube showing some parts of the fix.
I hope you make your fix easier with removing the wires so that you can reach all three 8mm head bolts to tighten up the mudguard when putting it back together.