All that's needed is a 2" PVC female coupler, a piece of 1/8" plexiglass (size 3.5 "x 4.5"), some industrial strength adhesive or strong glue & some sandpaper.
Step 2: Sand Edges
Next, lightly sand the edges of the piece of plexiglass, corners too.
Step 3: Glue
Carefully add glue to the edge of the coupling & set the piece of plexiglass on top. You don't need to press too hard, just give it light pressure to the top. I glued it off to one side so I can turn the mount around being I have a tight space where my cup holder is. This way you have more area for the suction cup to adjust for your specific vehicle.
Step 4: Let Dry & Install
After the glue sets up, install in cup holder. Attach suction cup to the mount & adjust your GPS.
Note- The black mount that's in my truck is one that I made a while back. I thought it looked better than grey. You can use a black ABS coupling if you want. I just wanted to show how to make these. Enjoy!