p870tm internal USB header + LTE USB WWAN

Hello Everyone,
I'm trying to add wwan functionality to an EVOC/Clevo p870tm and saw how one guy might have got it to work here:
http://forum.notebookreview.com/threads/anyone-added-wwan-to-a-p870-chassis.803565/page-2
But I'd just like to connect an LTE USB adapter to the USB bus and mount it internally somewhere.

Does anyone know where there are unused internal USB headers? I suppose I could disconnect the camera as an alternative option, but I would rather just find a spare header if there is one.

Are there service manuals or anything that might indicate where this could be?
Alternatively I think an SD Card that works as a wwan adapter could be good, but I don't know if it would get signal or if these things are still made. Closest I found was this:
https://www.slashgear.com/huawei-ultrastick-sd-card-brings-3g-internet-to-laptops-04300280/

Thanks for the help!

 

In terms of space there are the sata bays under the GPU bays.

 

In terms of space there are the sata bays under the GPU bays.

 

I'll probably put it in the bay for the 2nd graphic card because that's empty on my system. However I'm still not sure where to find unused internal USB headers.

Does anyone know of unused internal USB headers on a an EVOC/Clevo p870tm?

 

I couldn't find any spare headers, but the PCH has one unused USB3 channel, and 6 unused USB 2 channels (boxed in green below). Not sure how you could connect to them as the PCH is BGA and those pads are likely not broken out into traces, but you can have a probe around. Plus who knows if they are even enabled with the current firmware.

Another Idea would be to use a USB splitter on one of the eight USB 2 channels.

 

Power is the main issue splitting off.