This is a different argument. It's not necessarily saying consciousness is distinct from matter. The panpsychist view (not sure if Chalmers is in this camp) is that consciousness is a fundamental property to all matter, from photons to the human brain. (This isn't to say a photon has experiences as a human does, but rather the complex human consciousness is derived from a much simpler forms of consciousness).
This is different from saying ""where the car goes when you take all its pieces away?". This assumes consciousness is an emergent property, rather than a fundamental one. The "car" is emergent from the right arrangement of "car parts". Rather, the question "where is the mass/charge of the car when you take away all its pieces" is a better analogy, because the car mass/charge is derived from the mass of the car part's mass/charge.
>there's not enough evidence to test scientifically.
This aligns exactly with what Chalmers says, that explaining subjective experiences is the "hard" problem precisely because we don't have a way to gather data. Gathering data is, almost by definition, an objective measure and can't give much insight into subjective experience. To a certain extent, if feels like defining or measuring subjective experience can't be looked at with traditional scientific inquiry. Unfortunately, that can also lead to a bunch of quackery.
It's not even a good question unless they first prove consciousness can exist outside its physical support, AKA the immortal soul.