MO School bus law

MO School bus law
I got honked at yesterday for passing a school bus in the opposite direction on a four-lane road in St Louis. As far as I’m aware (and as the MO driving guide suggests), this is perfectly legal, but I’m worried sick that a report may be filed, given that I was honked at. Could you please confirm the law regarding this matter, and whether there will be a case?

Justin’s Answer
You must stop, even if coming from the opposite direction.