customize podcast archive – remove sidebar

Dear team:

I have tried what was suggested in one of your post about customizing the podcast archive area, however, it did not work. The suggestion is to take the archive.php, copy it and then rename it archive-podcast.php and then one is able to customize it. However, my theme (xtheme) does not contain an archive.php file. Apparently xtheme uses a wp-index-php file for that. When I changed the wp-index.php in the way described above and deleted the code corresponding to the sidebar within the php file nothing changed. I can still see the sidebar in my podcast archive. Can you help, please? I really would love to remove the sidebar for the podcast archive site. Thanks so much!

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