Hello Tim,
Yes, you are in a correct path. Just make sure that all your customizations were done in the child theme so that it will not be overwritten when there are theme updates. Assuming that you are using Integrity stack and has already set up the child theme, please do these steps below:
1] Using Notepad or TextEdit or Sublime Text or any text editor, please create a new file in your local machine.
2] Insert the following code into that new file
<?php
// =============================================================================
// VIEWS/INTEGRITY/_CONTENT-POST-HEADER.PHP
// -----------------------------------------------------------------------------
// Standard <header> output for various posts.
// =============================================================================
?>
<header class="entry-header">
<?php if ( is_single() ) : ?>
<h1 class="entry-title"><?php the_title(); ?></h1>
<?php else : ?>
<h2 class="entry-title">
<a href="<?php the_permalink(); ?>" title="<?php echo esc_attr( sprintf( __( 'Permalink to: "%s"', '__x__' ), the_title_attribute( 'echo=0' ) ) ); ?>"><?php x_the_alternate_title(); ?></a>
</h2>
<?php endif; ?>
<?php x_integrity_entry_meta(); ?>
</header>
Of course, do not forget to add your amp codes.
3] Save the file named as _content-post-header.php
4] Upload this file to your server in the child theme’s folder wp-content/themes/x-child/framework/views/integrity/
Create the folder path in your child theme because it does not exist yet.
Please let us know if this works out for you.