[DoctorOhh]

@ElLoco - itimpi gave you the best direct method.

Here is a little more detail and an image as a guide. In the GUI find the book in your library with the best metadata, highlight that book then highlight any books you wish to merge into one folder/book. Once they are all selected right click and drill down according to the attached image. This will combine all formats in one book/folder (the first selected) and delete the remaining folders. The plus here is you only have to perfect the metadata on one format then combine the rest.