With the anchor light and running light on, boats approaching from the forward 225 degrees will see a "standard" , if somewhat distorted, configuration, a side light and a white steaming light way up there. From the stern 235 degrees, an approaching boat will see two white lights, which I do not believe is a standard configuration, but boats approaching from the stern 235 will be on a similar heading, an overtaking boat will be the give way vessel, and boat that is not overtaking will not be much of a collision risk. I will admit it is not the perfect solution, but it seems to me a reasonable solution. Other options: toss a sweater over the stern light, duct tape a flash light to the bow rail, although most flashlights will not give you the correct angles. If your electrical system is unreliable, pick up a set of battery powered clamp on nav lights. You could declare that it is illegal to move the boat, turn on the anchor light, drop the anchor, open another bottle of wine and party till sun-up. Sort of like telling your date that you ran out of gas...