For the next few upcoming shoots I'll be using an all in one solution for recording video AND sound. Since I've primarily been shooting on Blackmagic's 4K production camera, sound has to be recorded separately and synched up in post which is very time consuming. Since recording directly to a recorder isn't the best option for good audio I bought a Sound Devices 302 mixer.
So, I'll be running audio from the a Rode NTG 3 to the 302 and then directly into the camera for good clean audio. Blackmagic had added an update a while back that let you monitor incoming line-level audio so now this is a feasible setup. Last time I ran this setup I just zip tied the mixer to the rail system, which works but isn't easy to remove and attach quickly as needed.
I am by no means a 3D modeler but I have been practicing Blender software for the past couple of months. However for my basic printing needs I use tinkercad. I modeled brackets to mount the SD 302 directly to my shoulder rig rails which are 15mm. I also designed a bracket to mount V mount batteries too.