Help with changing the layout of an area

I have a wordpress website that has been modified a little bit.

the way the site is set up is to use the theme to frame the page, then the “Pages” content fills part of the page and the “product listings” content fills other areas. (see below)
dashboard pic

what I have now is a page (see below) that has an area that says “Rebuilt and Used Equipment”
site pic
that pulls the “pages” content for the image and logo on top and the “product listing” content and generates the left pane (although this page only seems to pull the title of the post and not the content like other pages do). Each title is a different line.

product listings area

with this code in the php page

<div id="rebuild_head"></div>

<div id="rebuild_left">
    <div id="rebuild_header">
        <p>REBUILT AND USED EQUIPMENT</p>
    </div>

    <div style="height: 550px;" id="products_list">
        <?php
        $q = new WP_Query('post_type=cmgproductlisting&productcategories=rebuilt-and-used&showposts=0&orderby=title&order=DESC');
        $odd = false;
        while ($q->have_posts()) : $q->the_post(); ?>

        <div class="products_list_entry<?php if ($odd){ echo ' odd_product';}?>">
            <?php $img_src = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), 'thumbnail'); ?>
            <img src="<?php echo $img_src[0]; ?>" alt="" />
            <div class="products_list_entry_center">
                <h3 style="color: black; font-size: 110%;" ><?php the_title(); ?></h3>
<!--
                <?php $content = get_the_content();
                    $parts = split('<ul>', $content);
                    echo $parts[0];
                ?>
-->
            </div>
            <?php echo '<ul>' . $parts[1]; ?>
        </div>
        <?php $odd = !$odd;
        endwhile; ?>
    </div>
    <div id="rebuild_footer">
        <p>IF YOU DON'T SEE AN ITEM YOU ARE<br />LOOKING FOR PLEASE CONTACT US</p>
    </div>

</div>

What I would like to do is to change that area to a blank frame that instead fills with the post content and images that I provide in the “product listings” So I need a frame of a specific size that will use the

if ( have_posts() ) while ( have_posts() ) : the_post(); $this_post_name = $post->post_name;

like my other pages do to fill it

BUT, I am not up on how to make it work.