Simplification…
New and improved..
The bill I cut off the front of the hat is this nice thick plastic material. So, why not make a battery holder out of it?
I marked out the design…
Then, cut it out…
I used a soldering iron to heat the fold lines, and “plastic welded” it all together where the sides connected…
That actually made a nice solid battery holder…
I then drilled some small holes so I can sew it in place on the ball cap…