Go into the Admin CP
Styles & Templates --> Style Manager
In the drop down menu select "Edit Templates".
Postbit Templates --> postbit
Find:
<div class="smallfont">
<if condition="$post['joindate']"><div>$vbphrase[join_date]: $post[joindate]</div></if>
<if condition="$post['field2']"><div>$vbphrase[location_perm]: $post[field2]</div></if>
<if condition="$post['age']"><div>$vbphrase[age]: $post[age]</div></if>
<div>
$vbphrase[posts]: $post[posts]
</div>
<if condition="$show['reputation']"><if condition="$show['reppower']">$vbphrase[reppower]: $post[reppower] </if><div>$post[reputationdisplay]</div></if>
<div>$post[icqicon] $post[aimicon] $post[msnicon] $post[yahooicon] $post[skypeicon]</div>
</div>
Add After:
<if condition="$post['rank']"><div class="smallfont">$post[rank]</div></if>