Replacing widget element with a newly constructed DOM structure

<script>
(function( $ ) {

    $.widget( "my.dropbox", {
        errorText: function(text) {
            $(this.element).next().html(text);
        },

        _create: function() {
             var id = $(this.element).attr("id");
             var customDropbox = $(
                "<div class='form-group'>"+
                   "<label for='"+id+"'>"+getLabelFor(id)+"</label>"+
                   "<select id='"+id+"'></select>"+
                   "<div class='errors'></div>"+
                "</div>"
             );
             customDropbox.attr("id", id);

             $(this.element).replaceWith(customDropbox); // This removes original element from DOM

             populateOptions(id);
        },


    });

}( jQuery ));

$(document).ready(function(){
    $("#field1").dropbox(); //blank input field turns into a select with a label, populated options e.t.c..
    $("#button1").on("click", function(){
        $("#field1").dropbox("errorText", "This is a validation error message"); //throws an error saying dropbox is not initialized 
    });
});
</script>
<html>
     <body>
         <input id="field1" />
         <button id="button1">Press me</button>
     </body>
</html>

So I want a widget with public methods that will replace the original element with all the widget data associated with it. The problem with the above code is that the <select..> element is just a DOM element and if you call .dropbox(..) on it, it will say the widget is not initialized. Is there a way to make the select element into the widget object with the .errorText() method? All widget examples online add stuff around the original element but never replace it. As for the bigger picture, I'm trying to make a generic tool to configure forms dynamically. It's going to be all <input id="..."> in html but then javascript will query a database, get configuration for the field and turn it into a dropbox, checkbox or, say, a date picker with all the labels, validation, and other bells and whistles.