The taxi driver must possess a conversion table for the purpose. From Railway Stations From CST 20-30 mins by taxi. Taxis are available from the Chhatrapati Shivaji Terminus. TIFR is on the same road as the Navy Nagar bus terminus, which is where you should get off. From Bombay Central 30-45 mins by taxi.
Taxis are available from the ranks outside the station.
Alternatively, you could cross over to the local station and board a Churchgate bound local. You have to buy a separate ticket for the local train. Taxis are available from outside Churchgate.