I live in a victorian terrrace and have recently started removing anaglypta wallpaper with a view to skim the walls so that they are smooth to paint. Trouble is on removing the wallpaper we have discovered a layer of two more wallpapers underneath. One seems to be about 30 years old and the other maybe 50. They are simply NOT coming off. I've tried steaming, scraping, soaping! Any tips on how to get it off? Many thanks.