well...I go to the WP Desk, Appearance, Editor, I choose post.php. I copy it, then paste it in my "text edit", I change the name for "The Template Name Posts:Full Width Posts", them I took the side bar out. "" then I re-name the file as "fullpage-post.php", then I up load it with the FIle zilla in the Oxygen file. Also ive trayed chossing page.template-fullwide.php..but as the example before..NOTHING HAPPEND.
I've been surfing for millons of webs, forums, etc. looking for solutions...and I can tell that a lot of people has the same problem.