I have no idea why anyone would want to visit, let alone for two days--unless one is into conspicuous consumption. There were shuttle buses, but they only went to one of a variety of international style malls.
Vastness of India is pointed up by the change in geography between here (almost tropical) and Mumbai. Too many things to see in the time we had, and considering that our ship for some reason was docked in the industrial area rather than with other cruise ships. Shuttle buses are apparently blocked by the local taxi unions.