IIRC the best race at Monaco was in 1992 was the Senna & Mansell race, were that last 4 laps Mansell was all over Senna's car but could not pass (a lose wheel nut cost him the win) and he finishe 0.2 seconds behind, Mansell had to be help out of the car as he was totally knackered.
http://en.wikipedia.org/wiki/1992_Monaco_Grand_Prix
Mansell went on to win the title with 5 race still to win.