So just for fun, I took a piece of scotch brite to the "discolored surface" of my side housings (the ones that overheated).  I guess it was just a carbon coating because it came off in less than a minute of light rubbing.  Here are the before and after shots.  No evidence of cracks or distortion, so I plan to use them in my re-build.

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Dave Leonard
Turbo Rotary RV-6 N4VY
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