No one mentioned heat. I have freed several with penetating oil, propane heat and a tap tap tap over several days to a couple weeks depending on how frozen they are. Heat, spray, tap tap tap and walk off. Heat, spray, tap tap tap and walk off. Heat, spray, tap tap... It Moved!

Patience. You're working with a non-replaceable 70 year-old cast iron manifold.

~~ Jethro
1954 3100
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