If memory serves, in most of the Marin segments that aren't currently specified for bike access, that doesn't mean there's nothing at all - it just means that they're (usually) paved roads with no special provisions for cyclists. But motorists on the bayside of Marin are accustomed to cyclists on the roadways, so I wouldn't automatically suspect difficulty.
I haven't ridden that area since Bicycle Odyssey's closeout sale last year, but Sausalito up to San Rafael is pretty smooth sailing. I'm unfamiliar with the north end past China Camp, but Novato/Black Point/Sears Point looks pretty straightforward.
A long time back, the Metropolitan Transit Commission published the entire map in segments - sort of a collection of turnsheet-sized cards, with turnsheet instructions on one side and a route map on the other. They don't seem to list it for purchase as a physical set any more, but perhaps you can contact themto see if they still have one lying around.