Suppose that I am in Emeryville, CA, USA at 4-5 PM, having just stepped off the Amtrak California Zephyr train. How can I get to western Mountain View, CA with luggage including a large suitcase (28" × 20" × 10")? All of the routes I have learned of (BART or Capitol Corridor, followed by Caltrain in either case) are commuter trains, which are not known for their generous luggage space.

I previously made this exact trip via the Capitol Corridor train without being aware of its characteristics (thanks to Amtrak's route planner), and there did not seem to be any place for my luggage despite their luggage policy specifying that such size is permitted; did I miss a rack somewhere, or was I in the wrong car (as would be the case for Caltrain), or is it permitted but not actually practical?