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George Murphy can be a little elusive at times, but once you do make contact he'll ship the diaphragms out right away by Priority Mail. I used his product to repair all six vacuum pods in my 500SEC this summer. In my experience they work extremely well, but there is one problem that requires a little more work than his instructions prescribe.
The new diaphragm for the bottom half of the double pod, which George refers to as part #2020, comes with a little internal, plastic retainer cup. In theory, the cup and new diaphragm are simply pressed into the bottom cavity. In practice, that isn't nearly secure enough to work: as soon as you apply meaningful vacuum to the repaired pod, it will come apart. Behr didn't make the original pod that way; clearly, something stronger is needed. I discussed this problem with George, and a couple of solutions were bandied about, including glue. But what I ended up doing, and hopefully the attached photo will help clarify this, was to drill a small hole into the center of the bottom cavity and then screw the new diaphragm and its cup down with the assistance of two carefully chosen panel washers. The largest of these washers fit perfectly around the raised, central section of the diaphragm; the smaller washer applied force to the larger one underneath, pressing the whole assembly very securely together and making leakage impossible despite the creation of a small screw hole in the new diaphragm.
Permissible leakage from these pods is specified by M-B at 30mbars/min at 400mbars. When repaired properly, these pods will lose next to nothing over a period of several hours. In fact, I suspect that what little leakage I do see is caused by an imperfect connection between the vacuum gauge itself and the pod being tested.
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