Hi-
just had mine 2 weeks ago. Took 2 hours but mine was an "ICAO extended" as I already hold a license in another state, so that might have shaved a bit off. They tell you to allow 3 hours, and I think thats not far off if they are busy. There is a cafeteria/canteen on the third floor, the reception staff were all very friendly and will direct you where you need to go.
The 5pm flight I think would be pushing it to say the least, after allowing for security etc. Why make the day any more stressful? Book the later flight and bring a book/magazine etc, thats my advice.
Good luck and hope it goes well.
Vmo