For a dummy load you could wire a regular 1157 in line somewhere, say in the trunk. This will give you the necessary load for the flasher to work properly BUT if the bulb burns out then you have NO rear lights on that circuit. One thing you may want to consider is an LED indicator light on the GROUND side of the brake circuit. This small LED light can be mounted under the dash somewhere and will light when the brake lights go on. If anything goes wrong with the ENTIRE brake light circuit there will be no power going to ground and no LED indicator light. Soooo, if a wire falls off, light burns out or a brake light switch goes bad your indicator light won't light. How long has someone run around without brake lights and didn't know it?