Have existing formatting code. Need to add macro to new workbook.

Have a macro that reformats a newly opened workbook. (Items such as deleting columns, and inserting formulas in a couple of fields.)
Would like to have the aformentioned macro (which is located in another workbook), add this event handler private sub below in addition to reformatting the page as described. It adds a highlight row.

The code I'd like to add is this:

Private Sub Worksheet_SelectionChange(ByVal Target As Range)
    Cells.FormatConditions.Delete
    With Target.EntireRow
        .FormatConditions.Add Type:=xlExpression, Formula1:="TRUE"
        With .FormatConditions(1)
            With .Borders(xlTop)
                .LineStyle = xlContinuous
                .Weight = xlThin
                .ColorIndex = 2
            End With
            With .Borders(xlBottom)
                .LineStyle = xlContinuous
                .Weight = xlThin
                .ColorIndex = 8
            End With
        End With
        .FormatConditions(1).Interior.ColorIndex = 42        
    End With
End Sub

Thanks in advance for some direction on this.

Petee