They show (to me) pretty clear signs of being able to imagine people and things not in their presence, for one thing.

Spend enough time with dogs, and it becomes hard work explaining away that they are conscious, and most of the arguments you would come up with could be used to explain away that your neighbour is conscious, too.

You can’t prove that your neighbor is conscious. It’s the old “zombies hypothesis” from Philosophy Of Consciousness 101.

Since we're talking about consciousness right now - doesn't that mean it must have at least some impact on the physical world for our physical selves to even know about it? Just from that, I don't see how it's conceivable something could be physically identical if it lacks consciousness.

By that argument my home security system is conscious.