How do I select a face on a part to make a sheet metal

SF 2009-09-09

I have made a API where I import a DXF to a part and extrude it, and after words I want to select the face to make a sheet metal, but

the way I hav made the select is with this code

Part = swApp.ActiveDoc

boolstatus = Part.Extension.SelectByID2(

"", "FACE", 0.1451825637491, 0.1859651832025, 0.004999999999939, True, 0, Nothing, 0)

boolstatus = Part.InsertBends2(matthigness,

"", 0.1, -1, True, 0.5, True)

Part.ClearSelection2(

True)

It is working with som parts but not all, because of the coordinate for the face is not allways the same

What can I do to be sure that I allways select the face?