Its actually quite similar.
1) You will want to stop the aex-pluginmanager process
2) delete /opt/altiris
3) delete /usr/bin/aex* (there are quite a few and they are simply links to the real binaries in /opt/altiris
4) Remove the Symantec App from /Applications/Utilities
5) I no longer have anything in Startup Items but there is an item in /Library/LaunchDaemons (com.symantec.SMAgent.plist)
Might need to unload this first:
sudo launchctl unload com.symantec.SMAgent.plist
6) Remove the receipts from /var/db/receipts
7) Check that no other receipts exist
pkgutil --pkgs | grep altiris
pkgutil --pkgs | grep Symantec
7a) If more do exit you can remove them by doing the following:
sudo pkgutil --forget [packageID]
where [packageID} is the name of the package as it appears from above; something like com.Symantec.DeploymentSolutionAgent
Of course you could do some greps and pipes to make the cleanup even faster. It would also be pretty easy to write a script or even a package to remove the agents.