Power Query : space before text

Hi,

Here is my plain issue :

i've got a 2 column dataset

Lib           Nb_Pad
Pad1       1
Pad2       2
Pad10     10
Pad5       5

I've seen that using the formula Text.PadStart
it was possible to do something like this :

Pad_Lib

 Pad1
  Pad2
          Pad10
     Pad5

The thing is i'm not good enough to set that up in M.   -:)

I think of something like :

-------- M -------
let
    Source = Excel.Workbook(File.Contents("MyPath\Myfile.xlsx"), null, true),
    Order_Sheet = Source{[Item="Order",Kind="Sheet"]}[Data],
    Promote = Table.PromoteHeaders(Order_Sheet, [PromoteAllScalars=true]),
// insert a step here that will do the pading trick !!
    Pad = Table.TransformColumns(Promote, {{"Lib", each Text.Padstart("Lib", "Nb_Pad"), type text}})

in
    Pad
 
-------------

Thanks for your help !

Stephane