Newbie question: Upgrading to SAM 6.0.0

I want to upgrade our SAM environment to 6.0.0, while not upgrading any other environments. I am taking over this responsibility from another team.

My questions:

1)  Does the SAM upgrade require a stoppage of services? I realize that there are separate installs for Main, Poller & Web-only. I was curious if I needed to stop services before running the upgrade on the Main node first.

2) Is there anything else that I need to do besides running the install? Main -> Poller -> Web would be the order I go in.

3) Does the upgrade require a reboot?

Thanks - and sorry for the dumb questions.