6.1 Identifying UserID in BAM Custom Alert

I would like to include Vantage UserID in the body of the email that I
am sending when a Selling Price gets changed (the UserID of the person
making the change) I poked through previous Alert related postings and
saw the use of USERID but have been unsuccessful in getting it to work.
Any tricks to this? Any and all help greatly appreciated.

Sincerely,
Peter Dunbar
Halm Industries Co., Inc.