Looks good. I followed the same "sandwich" philosophy when mounting mine, utilized the HD pack lights, but went a little farther with the actual mount. Instead of utilizing all thread like is common for this type of project, I located some steel tubing and cut to length for added rigidity. Half of my pack is used for audio and I am considering acquiring a larger pack for travel. My next step is fabbing a mount using the HD dock so I can easily switch between the various packs.