On my first post, the width of the post is not 100%.

[Lynne]

This should work for the postbit template, you should be able to do similar with postbit_legacy if that is what you are using.

Find:

                <vb:if condition="$post['isfirstshown']">
                    {vb:raw ad_location.ad_showthread_firstpost_start}
                    {vb:raw ad_location.thread_first_post_content}
                </vb:if>
                <vb:if condition="$post['islastshown']">
                    {vb:raw ad_location.thread_last_post_content}
                </vb:if>
        <div class="content<vb:if condition="$show['first_ad'] OR $show['last_ad']"> hasad</vb:if>">

Change to:

                <vb:if condition="$post['islastshown']">
                    {vb:raw ad_location.thread_last_post_content}
                </vb:if>
        <div class="content<vb:if condition="$show['last_ad']"> hasad</vb:if>">
                <vb:if condition="$post['isfirstshown']">
                    {vb:raw ad_location.ad_showthread_firstpost_start}
                    {vb:raw ad_location.thread_first_post_content}
                </vb:if>

Adjust padding around ad as needed.