Has anyone taken apart a lens in order to clean it? I have a Nikon 200mm F4 micro lens (manual focus) that has something nasty on the inner lens surfaces, and an obvious blob of something. My concern is that it is the early stages of fungus hence my desire to remove it before damage is done. I've got quotes for cleaning, and they are more than the lens is worth i.e. I can buy a new (used) lens for less! So I'm considering DIY cleaning.
I'm told that I need an optical spanner wrench for removing the retaining rings, and I have jewellers screw drivers. I'm well used to cleaning the external lens surfaces, so the actual cleaning should not be too difficult. But I'm a little concerned that there might be a nasty surprise or two waiting for the unwary. In particular, if I end up removing a lens element, how do I remember which way round it goes back on, or will this be obvious? I am tempted to use little dabs of liquid paper, or a marker pen.
Hints and tips welcome!