Erm, after clear JB custom, no need walk to jb sentral take bus, just walk straight abit more and go down escalator back to bus level take any public bus, yellow or sg 170 to larkin.
Yeah, that's true, in fact we went there too, but on the day of our travel, the buses from Singapore were few and far between. I reckoned it would be faster to take the local bus. ☺️