If you are going to tackle this one, you need to get the CD. Yes, it sounds like the head gasket is gone. Yes the exhaust manifold has to come off. Removing the water pump isn't necessary to remove the head.
While the head is off, I'd suggest taking it to a machine shop that specializes in rebuilding heads and at least have it checked for cracks and warpage. For around $300, you can have the head completely rebiult. IMO, a good idea.
I would not attemt this without the CD though.
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