3rd member gasket leak

Found the culprit! Gasket tore at the bottom at some point.

Well I would use a gasket but I doubt anyone has one in stock, I'm going to look right now.

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That is a common place for it to tear, as the housing does not support it very well there. If you fumble at the install, it likes to tear there. If you back it up or remove it, it still likes to snag and tear there.
I have never used any sealants or glues, just the dry gasket.

I agree with Oldmanmopar that the weld is somewhat prone to leaking.