OK, got it done. used propane torch and wire brush, clean as can be...though the color is now a cool, bronze-ish/titanium-ish color; the black anodization is gone. Thanks for all your help!
One last question on this, take a look at the photo below; the tall one is the old/cleaned up retainer, which was married to a 4" tailcone, and the shorter one is a brand new, 'plain' retainer....and you can see a damaged, but perfectly usable, spacer that came with the tailcone-set, as the 'retention-space is oddly large compared to my new retainer (that actually accounts for most of the extra height).
My question is....is the tall one tall because it was partnered with the tailcone, or was it tall for some other reason, i.e. it needed that extra 'retention-space' for older motor hardware or something? Cuz I want to use the tailcone on my new build, but the old retainer came from a phenolic (thicker) MM tube & is too loose for the thinwall glass I'll be using. But if I use the short retainer w/the cone, am I doing something wrong?
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