It's very easy to connect a rear light to a SP700, I've done that today. This light (to install at rear, fixed on a frame screw) will automaticaly turn on when you'll select reverse mode.
You must connect the ground wire of your rear light to the purple wire belows head lamps. To find this purple wire (ready to be connected), you must remove, first, the front rack, then the front cover. In fact, it's 2 purple wires witch are connected together. Easy to find.
After connect the ground wire of your rear light to the purple wire, connect the 12V wire of your rear light to the 12V battery (with a fus if possible).
That's all, it's works perfectely, when you select reverse, your rear light will turn on automatically !
Just be carreful to not inverse wires. Do not connect 12V light on the purple wire but ground wire. If you inverse wires, you'll obtain a "E" (error) message on the "Rider Information Center"
Have fun.