$(this+" ul not working

$(this+" ul not working

I'm pulling my hair out of this one.

I have developed a few jquery plugins, but of course the all fail when multiples of them.

So to use, 'this' prior to each element call is needed, but I can't get it to work.

eg: var Items = $(this+" ul li").size(); will not work.

Hope someone can point me in the right direction!

Markup and function here:

<!-- START OF CHANGER -->
    <script type="text/javascript" src="/structure/js/scripts/changer/changer.js"></script>
    <script type="text/javascript">
$(document).ready( function() {
     $(".changer").changer({
Delay: 4000,
Speed: 500
})
    });
    </script>
    <div class="changer">
          <ul>
                <li><img src="/structure/images/debug/image1.png" /></li>
<li><img src="/structure/images/debug/image2.png" /></li>
                <li><p>Textual</p></li>
                <li><img src="/structure/images/debug/image3.png" /></li>
  </ul>
    </div>
    <!-- END OF CHANGER -->

(function($){

$.fn.changer = function(options) {

$.fn.changer.defaults = {
Delay: 4000,
Speed: 500,
Animation: "SlideUp"
}

var option = $.extend({}, $.fn.changer.defaults, options);
    
    return this.each(function() {
    
var Height = $(this).height();
var Item = 1;
var Items = $(this+" ul li").size();
$(".changer ul li").css("top", Height);
$(".changer ul li").each(function(index, object) { 
index = (index*1)+1;
$(object).attr("id", "changer_"+index)
});
play = setInterval(function(){
$(".changer ul li").animate({top: Height}, 500 );
$("#changer_"+Item).animate({top: "0px"}, 500 );
if ( Item >= Items ) {
Item=1;
}
else
{
Item++;
}
}, 2000);
});
    
}
})(jQuery);