ServiceDesk 7.5 - mask SSN (in Rules?)

In Helpdesk 6 we use an Incident Rule to mask any Social Security Number (SSN), we blank them out with Xs - XXX-XX-XXXX, we were hoping we could accomplish something like this in ServiceDesk 7.5.    Anyone have a solution in Rules?  Or in the Workflow? 

Here is our Incident Rule:

Name: MASK SSN in E-mail Sent as Helpdesk Incidents
 
Comment: This rule will REPLACE a SSN with 'XXX-XX-XXXX' in a ticket in e-mail or manually saved

Set these properties:  Set "Comment" to "HDQUERY[[SELECT REPLACE ((Cast(Comment as nvarchar (max))),(SUBSTRING(Comment,PATINDEX('% [0-9][0-9][0-9]-[0-9][0-9]-[0-9][0-9][0-9][0-9] %', Comment) + 1, 11)),'XXX-XX-XXXX') FROM workitem with (NOLOCK) WHERE number = WORKITEM (workitem_number) AND is_last=1]]"

When:  Every time incident is saved
 

And:  When ALL of these are TRUE
   "Comment" matches regular expression "^(\d{3}-\d{2}-\d{4})|(\d{3}\d{2}\d{4})*$" 
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Any help is appreciated.