You could simplify it and the following should only apply to the selected text:
Code:
Sub Macro32()
With Selection.Find
.ClearFormatting
.Replacement.ClearFormatting
.Text = "^t"
.Replacement.Text = ""
.Forward = True
.Wrap = wdFindStop
.MatchWildcards = False
.Execute Replace:=wdReplaceAll
.Text = "="
.Replacement.Text = "^t^&"
.Execute Replace:=wdReplaceAll
End With
End Sub