Same as you, 07 S2R 800...
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I tried to take pics when I installed but did it at night in a not very well lit garage so none really came out...
I did fit the alarm box and the perimeter sensor under the seat. The install went pretty straightforward and easy... I rerouted the power line a few times to find the best placement, pretty much right under the tank hinge and along side the [looks like a heat sink?] at the front of the seat. The box itself went just behind the [heat sink thing]. The only real modification I had to make was to remove the lid to the underseat box as the alarm box pressed up into that space. I got the Monster factory harness and everything plugged right up, no cutting or splicing wires...
I'll try to remember to take some pics tomorow...