Rocker cover gasket replacement - Peugeot 406 2.0 HDi 110

How to remove the rocker cover on a 2.0 HDi engine and replace the rocker cover gasket. The engine is the DW10ATED (110) or DW10TD (90) 2.0 HDi engine fitted to a 406, and a load of other PSA stuff. I noticed a bit of mucky oil mess round the back of the engine as i like to keep it clean. Thanks to a guide a fellow 406oc member captain jack made i was able to get the rocker cover gasket changed. Hopefully this will keep the top of the engine clean, i dont think it was a serious leak as i never noticed a change on the dipstick. There is a possibility that the air doser on these 110s can leak oil but i dont think mine is, and i cant see any oil line going to it, so any comments on what an air doser does or how it can leak oil are welcome. I used the spare engine i have from the spare parts 406 to show how to remove the upper timing belt cover, this would have been a very handy thing to have had when i was changing the timing belt. Hopefully you this view will help you find the bolts