For anyone deciding to have a go at stripping a lens, it is a good idea to get hold of and use JIS screwdrivers. The Japanese Standard Screwdrivers have a different face to the usual Philips or star driver which is most common. I've successfully clean a cannon 70-200L's front lens only after finding instructions online of which there are some. Maybe look around to see if the lens you mention has cleaning intruction online somewhere. Otherwise I'd go with Lightmancer ad get a pro to do it. Yet it is a satisfying achievement to do it oneself if all turns out ok.