Hi Robert.
I use this "script" and test by snmpwalk.
Clear snmp default
clear snmp access ro security-model v1
clear snmp access ro security-model v2c
clear snmp access public security-model v1
clear snmp access public security-model v2c
clear snmp access public security-model usm
clear snmp community public
clear snmp group ro ro secu v1
clear snmp group public public sec v1
clear snmp group ro ro security-model v2c
clear snmp group public public security-model v2c
clear snmp group public public security-model usm
clear snmp user public
Configure snmpv3
set snmp group
user security-model usm
set snmp user authentication sha encryption des privacy nonvolatile
set snmp access security-model usm privacy exact read All notify All write All nonvolatile
Test snmpwalk
snmpwalk -v 3 -a SHA -A -u -x des -X -l authPriv