Thanks to Edward for sharing:
As you can see in the attached images, the gun depression was dramatically buffed (it still looks weird, the angles are pointed in random directions) and it allows -10 to the front and some more to the back, when it only allowed -5 to the front before. I have tested this in-game on the test server and it matches.
Also, the gun model for the 105mm gun is much longer now.
Old model:
New model: