i have a bit of experience in this matter. The lower seals seem to fail under sustained boost or over a period of time - 10 - 15 k. The only reason i can see this happening is that the holes for the seals cannot be machined deep enough and you are basically using only half of the area to seal against leaks. Even if they don't fail on install they are likely to fail soon.
Harry
Formerly yellowzxtt
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