I am currently at the tail end of moderising my house. I have now realised that the light switches / hanging lights are all metal but have no proper earthing. I do not really want to replace all the lighting rings as the house is in a near finished. I have worked out that I could run earthing cable for all the light switches and 75% of the lighting roses (The rest I could replace with plastic roses) via some chasing of the walls and lifting the floor boards back to the consumer unit. Which would minimise the mess Is this a viable option?