So I managed to find a way to name my USB3 Video devices so OBS doesn't just show "USB3 Video" for the 5 USB 3 capture devices that I have connected to my computer. Here's what I did and hopefully I've explained it well enough that someone else can benefit from this. Please note that modifying the registry has the potential to really corrupt Windows and so anyone who attempts this should proceed with caution. I've copied and pasted the info and attached a text document for anyone to download.
To change a devices name in Device Manager get the "Properties" for a device then select and copy the "Driver key" under the "Details" tab.
Next open RegEdit and go to the following folder.
Computer\HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Enum
Search for the copied "Driver key" and change the "FriendlyName" key to your new device name.
I.E. Camera 1, Camera 2, Audio Mixer, whatever you want to name the new device.
Next, to get the same device name to show up in OBS copy the "Device Instance path" in the "Details" tab and search in the following folder.
Computer\HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Control\DeviceClasses
Turn the tab and go to.
#GLOBAL\Device Parameters
There will be two of these key folders.
Look for and use the folder that has both a "Device Parameters" and "Properties" folder.
There will also be a "FilterData" key in this "Device Parameters" folder but not in the other one.
In the "Device Parameters" folder change the "FriendlyName" key to the same name as in the previous "FriendlyName" key.
****Note the names will change if the interface is plugged into a different usb port****
