Manager - SNMP option

I am currently playing with SNMP option in Manager. I have some luck in getting SNMP Agent installed and worked. Now, I have trying to reset or clear the SNMPVariableFilter and SNMPInstanceFilter without any luck. I have totally removed the SNMP configuration properties files from the Controller and the result the same.

I was tempted to drop some tables from ANALYSIS schema that defined SNMP settings BUT afraid to do so.

Do anyone have done this before ? Any suggestion to purge these two filter is greatly appreciated.