I finally found a diopter that fits the GH2 EVF, it the Sony FDAECF30 Diopter +3 correction lens. I bought two from Walmart, removed one of them from it's housing, and glued it to the camera (bottom) side of the one still in it's housing, then stuck it right up against the GH2 evf lens, and secured it with a bit of tape around the edges. Now I can really do documentary style follow focusing with a wide lens ! If you have better eyes than me, you might just need one instead of two.
When you get a chance, can you post a pic of the diopter attached to the camera?
Here it is before cosmetics. The bits sitting on the back of the screen are the two parts of the housing that held the second lens. If you can make do with a single +3, it doesn't protrude at all...
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