In the photos above Obi wan is a no neck sculpt, Einstein is a full neck sculpt. Kennedy and Lincoln are partial necks. I also used 2 different bodies. I bought both on Amazon the Lincoln and Kennedy bodies were
https://www.amazon.com/gp/product/B00UV7QAHO/ref=oh_aui_search_asin_title?ie=UTF8&psc=1
And the Einstein and Obi wan were
https://www.amazon.com/ZYAQ-Narrow-...SEC8SJA8TQN&psc=1&refRID=648769156SEC8SJA8TQN
As you can see, the first body had a full neck.
I printed all but the Einstein head on printer. As you can see from the above image, I include the insert for the ball joint just behind the jaw and at the base of skull.
The ZYAQ body came with various neck joints to connect to. The Einstein head was attached similar to this image below,
Notice the brown neck insert at the base of the Kalakaua head sculpt above.
I'm attaching it to a ZYAQ body using their neck insert.
Since his is a casting of the original 3D head (as was Einstein's) I have to drill a hole in the base of neck the same diameter as the insert. Then I use plumber's epoxy putty to transition the neck neck to the insert. At this point I also use the putty if I need to make the neck slightly longer, drilling the hole only deep enough to fit the top of the pin and leaving a gap that I fill with the putty.
In your case, you won't need to drill if you're using an actual print as shown in your picture. If you're using the neck insert that came with the body, you will have to make sure that your print neck is long enough. If you're going to use the articulated neck attachment, you'll have to either model the hole for the ball joint before printing, or you will have model it with putty after the print arrives.
However - the first method does not work on the body with the attached neck. You will need to design your own insert in the print to make it work properly. Hope that was helpful.