Try:
<style type="text/css">
.two_columns {float: right;}
.col_1 {width: 300px; float:left; margin-right: -320px;}
.col_2 { float:left; margin: 0 190px 0 320px;}
.col_3 {width: 300px; float: right; margin-left: -190px; }
</style>
<div id="doc3" class="yui-tvb-l3">
<div class="two_columns">
<div class="col_2">
<ul class="list_no_decoration widget_list" id="widgetlist_column2">$column[2]</ul>
</div>
<div class="col_3">
<ul class="list_no_decoration widget_list" id="widgetlist_column3">$column[3]</ul>
</div>
</div>
<div class="col_1">
<ul class="list_no_decoration widget_list" id="widgetlist_column1">$column[1]</ul>
</div>