Skip the first two bits, not worth the effort. I would do Mother house first thing, then a taxi to Victoria, then take a taxi to Babughat or Fairlie ghat, take the ferry across the river to Howrah station for a quick look, then the ferry back to Fairlie ghat and walk to the GPO and past writers building to Barabazar. Marble Palace is very close that if you have time. Then take a taxi to the Oberoi, or even better the metro, which bypasses all traffic. If you have energy left, walk thru new market which is right behind the oberoi.

I made Newbie Runner and Xyzzy do all that in peak summer this year:
https://plus.google.com/photos/10431...273?banner=pwa