I created a voltage display for the Airsoft Mosquito. I included the Fusion 360 file and Step file. I used the voltage display at the below link. It is tight enough that the voltage display didn't need to be secured. Mounting holes are 3.5mm OD. I drilled the 2 mounting holes and made one of the existing holes larger for the wires to pass through.I wired it to the motor side using JR Servo Extension wires so it could be disconnected.
https://www.amazon.com/dp/B07Q2RQYPJ?ref=ppx_pop_mob_ap_share
The author remixed this model.