Actually, we found the sort of thing I had been looking for all along. When you right click the tag there is an option for "edit schedule data" where you can manually imput the information for the tag if desired. One would imagine that there would be some sort of "advanced" button in there so that you could add prefixes to all the room in that drawing, or in this case change the precision of the data. Oh, but no, you have to go to the pulldown menu Documention > Schedule Data > Data Format Styles. Once anyone's there they can figure it out.
Sorry for the waste of time but thanks for the help.
And no, this was not a lisp routine, just a schedule tag we made and put in the design center.