off topic but I wanted to answer Ironglows suggestion about weed whacker line.....
I checked my orange line and it was too big. but your suggestion made me start thinking along that line and I found the perfect answer to cricket sights.
I stripped a piece of insulation from a tiny wire from a defunct telephone, slightly longer than the sight blade. slit one side the length of the blade dab some super-glue gel and slip it on. this gives you a small round thing that will hold a dab of paint, fingernail polish etc. worked great.
I hope this made sense. the sight blade is very thin on top and hard to see. this is the solution.
btw, when I say that I did something, it's usually my wife doing it.
I shake too much for fine work.