Regex Search/E-mail Users

[tpearl5]

Lets say I have a custom profile field that allows a user to enter a model number of a DVR box. The model numbers have a similar pattern ###ABC . But there are about 25 different ones. I want to do a regex to search for all members that match this pattern of model number. I know what the regex is, just not how to modify the search (/admincp/user.php?do=modify) and (/admincp/email.php?do=start) to accommodate a regex.