Took less than an hour and a half. Most was to find the right tools and to figger out where that slot went. I'd have liked one more slide showing the slot from the back of the bike. After examining the bike it was evident what was needed, though. I also had to retrieve two, 2, more than one, friggin screws from the depths below the seat lock. Stoopid.
I suggest that anyone else installing one of these lights stuff the bottom of the cavity with rags or paper to the level of the bottom screw before taking out and re-installing the screws.
One of the best deals about this light is that I did not even have to Think about playing electrician. Snapping in the connectors was a dream compared to most electrical accessories, and I'm not going to be worrying about the connections going down the road. When it comes to brake lights, that means a bunch.
It looks great, and is Very bright. Thanks!
If anyone in the Denver area wants a hand with installation, I'll guarantee it will be done in 30 minutes!