use 2 m3x6 screw
tap screw hole with m3*0.5 tapping tool
GPS module is https://item.taobao.com/item.htm?spm=a1z09.2.0.0.5b0e2e8dqmIzys&id=709639348086&_u=s25ao8rm1353
The author marked this model as their own original creation.