To start out I had purchased a Petzl Zipka Plus Headlamp. This has a string headband which is not my favorite but I had other plans anyway.
After that I purchased the Petzl Adapt kit.
It has a proper head strap, and various backs to fit different Petzl Headlamps. They also come with a Belt clip and helmet clip. I can now conveniently remove the headlamp from the strap if I want.
I modified the belt clip to mount on the dash for a dash light. The zipka Plus has both a white LED and a red LED bulb.
I then took the helmet mount from the kit and put on the ceiling of the SMB.
So now I have a separate reading light (red or white) mounted on the ceiling.
The Zipka Plus takes three standard alkaline AAA batteries, lithium AAA batteries and it will take the Petzl Core Rechargeable Battery.
A nice feature of the core battery is that you can program the output to be regulated get the max output or less output and extend time. It gives you a pretty flexible headlamp. It also charges off a standard USB port.