That's what I would do as well. Time? Well, it all depends on how lucky you get in the wait for the bus. You might walk up to the bus stop as the bus is arriving, or you could have a wait of 15 mins. But once you get on the bus, it takes about 10 mins to get to BW or YC/BC. Then, it's about a 10-15 min walk, through the Intl Gateway and onto LeCellier. I would say leave an hour and you'll most likely be early.
If you take the monorail it's going to be about the same. I just like entering through the Gateway since it's closer to LeCellier that way.