As far as lubricant goes, I've been adding a drop or two of standard light oil into a thimbleful(approximate) of naphtha, and after the cleaning with straight naptha I apply this very thinned oil solution to the bits. The naphtha evaporates and leaves a tiny thin amount of oil, too thin to possibly migrate or pool. So far it's been working fine.
I don't apply it to the diaphragm or shutter though, just the gears and widgets for some protection against corrosion.
As for grease, I just use very very small amounts of ordinary automotive green axle grease from a grease gun. Oh the horror.

Of course I don't apply it with the grease gun.

Hardly any really, just a small dab on my finger tip, and then only to the helicoil(sp) area of a lens.
And that's about it for lubricants.