Here is what we are doing for KEXT :
As far as installation we are dropping to staging folder and using script to execute.
# This script installs the Carbon Black 6.1.3 client and will uninstall the old client when applicable
# This will uninstall any previously installed McAfee agents, remove comment when ready
# This will install the Carbon Black client for Mac's
/usr/sbin/installer -package /Library/Staging/Packages/CarbonBlack18.104.22.168124/CarbonBlackClientSetup.pkg -target /
chflags hidden /Applications/CarbonBlack