Well it worked (and the steering lock does as well). It's not the most elegant solution but it's solid so I'll see how it holds up to riding and then possibly adjust it a bit later if I need to or get some nicer looking hardware. I wanted it to be simple without requiring any real custom work or modification of existing parts.
What I did was remove the plastic bushings from the bottom of the OEM triple...the ones that would normally sit inside the U bracket. I pressed them into the bracket directly. With the smaller bracket that holds the air temp sensor, I enlarged the holes just a little so that an M6 bolt fits through them (which is just slightly larger than the opening of the bushings). I mounted the gauges on top of that and ran a 50mm M6 bolt through it. On the bottom, I used a nut to tighten the bolt up against the gauge housing then used a 25mm nylon spacer to provide support for the smaller bracket, and then threaded the remaining end of the bolt into the nylon bushings in the U bracket to keep the smaller bracket from moving forwards or backwards. It basically mimics the original mounting method. You can see there is a little bit of a gap between the nylon spacer and nut so it's not really supporting the weight of the gauges per se but after some riding I'll try and close that gap up.
The next little project is painting the windscreen to match the OEM windscreen colors. I think the OEM windscreen looks a little too wide for the bike whereas this one keeps the lines slimmer. Plus the OEM one partially blocks the turn signals.
Thanks to everyone for their suggestions and especially caperix for planting this idea in my head. Total cost was about $100 for the bars and clamp used on ebay and a few dollars for the hardware.
