How to give anchor position in rich marker google map?

Hi I am using richmarker for custom image markers on google map in ASP.net MVC web app.
It’s working fine for normal markers. But I have some scenarios in which there are two markers at same location . Using default marker I am handling this by using Roadside LHS or RHS and specifying different anchors for LHS and RHS.And it works fine. But for rich marker, how to specify anchor so that I can see 2 separate LHS and RHS customized marker?

This is my code for rich marker.

           var marker = new RichMarker({
                                    position: myLatlng,
                                    label: data.RoadSide,
                                    map: map,
                                    title: data.title,                                         
                                    content: '' +
                                        '<div class="customMarker"style="float:left"><img class="" src="' + image+ '"/></div>'
                                });

Default marker for LHS and RHS:

    if (data.RoadSide == 'LHS') {
                                var marker = new google.maps.Marker({
                                    position: myLatlng,
                                    label: data.RoadSide,
                                    map: map,
                                    title: data.title,
                                    icon: {
                                        url: 'http://maps.google.com/mapfiles/ms/icons/green-dot.png',
                                        size: new google.maps.Size(39, 40),
                                        scaledSize: new google.maps.Size(39, 40),
                                        anchor: new google.maps.Point(15, 0),
                                        labelOrigin: new google.maps.Point(-20, 20)
                                    }
                                });
                            }
                            else {
                                var marker = new google.maps.Marker({
                                    position: myLatlng,
                                    label: data.RoadSide,
                                    map: map,
                                    title: data.title,
                                    icon: {
                                        url: 'http://maps.google.com/mapfiles/ms/icons/green-dot.png',
                                        size: new google.maps.Size(39, 40),
                                        scaledSize: new google.maps.Size(39, 40),
                                        anchor: new google.maps.Point(-20, 0),
                                        labelOrigin: new google.maps.Point(60, 20)
                                    }
                                });

                            }