I just got a 150mm lens for my newly acquired RZ67 body. It's in perfect condition, aside from the ridiculous amount of dust between the lens elements (which is why I got such a good deal on it...). So I figured, I'll just take it apart and blow the dust out. Easier said than done, it seems. I've got a 90mm K/L and had a 127mm K/L for the RB67, which are essentially the same lenses as the Sekor-Z, and I was easily able to disassemble those. I've got a spanner wrench that easily unscrewed the rear element on the 90mm K/L, but it won't move on the RZ lens, even when I used a terrifyingly dangerous amount of force extremely close to perfect glass. I'm stumped as to how to remove the front element, as well. Am I missing something here? Are the threads on the RZ lenses perhaps reversed just to mess with me? Does anyone have a copy of the lens repair manual they're willing to share?