I have a 166.065 in good condition if that would help. Diameter of the threaded part is 31.39mm. I'll leave you to do the measuring of the 166.002. Cost is postage to USA, about $2 Aussie. Yoo hoo @kingsrider
Excuse the dust. Ignore the halo mark, it's a reflection from my camera stand (plastic tub with a hole in the bottom).