Is it possible to setup the lightmap coordonate index with blueprint or Dataprep?

Hello

In my project i use a glb in which objects have two or three uv sets. I want to use the last uv set as lightmap coordonate index. If i use dataprep, i need to create an operator, but i’m not able to cast the element Object reference to the datasmith mesh element needed by the lightmap coordonate index. Is it possible? Or does another solution exist to do this with an editor Utilities or something else?

Thank you