SOLVED
This was my process:
File: header.php
Original Code Line: <?php wp_nav_menu( array( ‘container_class’ => ‘menu-header’, ‘theme_location’ => ‘primary’ ) ); ?>
Revised Code Line: <?php wp_nav_menu( array( ‘container_class’ => ‘menu-header’, ‘theme_location’ => ‘primary’, ‘menu’ => get_post_meta( $post->ID, ‘MenuName’, true) ) );?>
Also: “Then create a new custom field called MenuName and give it a value matching the name of the menu you want that page to use.”
Solved – just moved code from header.php into page.php