I have an assembly of curved surface parts (.10 inch thick) and need to create attachment holes in the assembly going through these curved surfaces into the structure. see image. (right now the image shows the holes in part level)

I need to dimension the point in hole sketch to the external structure(at assembly hole feature) but solid works doesn't let me pick the curved surface edge or structure edges.

I have unchecked the do not create reference external to the model option as well.

Has anybody faced similar problem before? if so any suggestion on creating assembly holes on curved surface?

Thanks in advance