I have designed a 10 x 10 cm panel for three functions:

• The first is to hold the cables of the servos and that these don't get disconnected.
• The second is to hold the connector of all physical grounds of the servos.
• The third is to hold the connector of all Vcc connections of the servos.

Below you can see a picture and download the STL file on my GitHub repository here:  https://github.com/guillengap/guillengap-robot-arm