functions.php

<?php

/**
 * Remove items from grid posts
 *
 */
function be_grid_post_customization() {
  // make sure we're on a grid post
  if( !in_array( 'one-third', get_post_class() ) )
    return;
    
  // Remove items we don't want
  remove_action( 'genesis_post_content', 'genesis_do_post_content' );
  remove_action( 'genesis_before_post_content', 'genesis_post_info' );
  remove_action( 'genesis_after_post_content', 'genesis_post_meta' );
  
}
add_action( 'genesis_before_post', 'be_grid_post_customization' );