I wanted to make something that could easily be adjusted by someone with mobility impairments as well as installed and removed from the wheelchair without tools.
There were two mounting options: Headrest support and arm support.
I figured mounting off the headrest support would put the mirror closer to the head and eye and also reduce the required length of the flexible arm.
Step 1: Materials and tools
2" mirror on 16" flexible shaft - $5.99 from Harbor Freight
5/16" eyebolt - The eye of the eye bolt acts as a handle for tightening the end of the bolt opposite the wing nut.
5/16" wing nut
(2) 5/16" washers
Step 2: Cut handle to fit headrest mount
Next, cut the handle lengthwise from the tip to the previous cut line.
Save the cut-off for clamping the handle to the headrest mount.
Hold the two pieces together and drill a 5/16" hole through both.
Step 3: Mounting
Haven't tried it out, as I need to get it there, but will post a picture after it is installed.