Search box uses a graphic to create that rounded corner effect which merge into upper green border. I am not sure it will be easy but yes can be done. I need to install theme , make modification and then suggest you here. I would have loved to help you but currently I am very much occupied. However, to give you head start, all you need to do is to find following code (it is code responsible for userarea) and copy it to desired location, you will need to make some css modifications also :
<div class="user">';
// If the user is logged in, display stuff like their name, new messages, etc.
if ($context['user']['is_logged'])
{
if (!empty($context['user']['avatar']))
echo '
<p class="avatar">', $context['user']['avatar']['image'], '</p>';
echo '
<ul class="reset">
<li class="greeting">', $txt['hello_member_ndt'], ' <span>', $context['user']['name'], '</span></li>
<li><a href="', $scripturl, '?action=unread">', $txt['unread_since_visit'], '</a></li>
<li><a href="', $scripturl, '?action=unreadreplies">', $txt['show_unread_replies'], '</a></li>';
// Is the forum in maintenance mode?
if ($context['in_maintenance'] && $context['user']['is_admin'])
echo '
<li class="notice">', $txt['maintain_mode_on'], '</li>';
// Are there any members waiting for approval?
if (!empty($context['unapproved_members']))
echo '
<li>', $context['unapproved_members'] == 1 ? $txt['approve_thereis'] : $txt['approve_thereare'], ' <a href="', $scripturl, '?action=admin;area=viewmembers;sa=browse;type=approve">', $context['unapproved_members'] == 1 ? $txt['approve_member'] : $context['unapproved_members'] . ' ' . $txt['approve_members'], '</a> ', $txt['approve_members_waiting'], '</li>';
if (!empty($context['open_mod_reports']) && $context['show_open_reports'])
echo '
<li><a href="', $scripturl, '?action=moderate;area=reports">', sprintf($txt['mod_reports_waiting'], $context['open_mod_reports']), '</a></li>';
echo '
<li>', $context['current_time'], '</li>
</ul>';
}
// Otherwise they're a guest - this time ask them to either register or login - lazy bums...
elseif (!empty($context['show_login_bar']))
{
echo '
<script type="text/javascript" src="', $settings['default_theme_url'], '/scripts/sha1.js"></script>
<form id="guest_form" action="', $scripturl, '?action=login2" method="post" accept-charset="', $context['character_set'], '" ', empty($context['disable_login_hashing']) ? ' onsubmit="hashLoginPassword(this, \'' . $context['session_id'] . '\');"' : '', '>
<div class="info">', sprintf($txt['welcome_guest'], $txt['guest_title']), '</div>
<input type="text" name="user" size="10" class="input_text" />
<input type="password" name="passwrd" size="10" class="input_password" />
<select name="cookielength">
<option value="60">', $txt['one_hour'], '</option>
<option value="1440">', $txt['one_day'], '</option>
<option value="10080">', $txt['one_week'], '</option>
<option value="43200">', $txt['one_month'], '</option>
<option value="-1" selected="selected">', $txt['forever'], '</option>
</select>
<input type="submit" value="', $txt['login'], '" class="button_submit" /><br />
<div class="info">', $txt['quick_login_dec'], '</div>';
if (!empty($modSettings['enableOpenID']))
echo '
<br /><input type="text" name="openid_identifier" id="openid_url" size="25" class="input_text openid_login" />';
echo '
<input type="hidden" name="hash_passwrd" value="" />
</form>';
}
echo '
</div>';
I hope that helps. I am assuming you have basic knowledge of php and css etc. to make this edit yourself.