Need some help joining a head and a body

Hello everyone, I've used Blender before a long time ago and am just getting back into it. I'm trying to make a snake here and I've already made the body and the head. The head is two separate bones, one for the top and one for the bottom jaw. I am trying to connect them both to the body and make the meshes merge so the head looks like it's part of the body without clipping through it. Does anyone have any ideas on how to do this? Here's a link to my file since it was too big to directly upload here. 

https://drive.google.com/file/d/1LovdUzUgjALp0kKDtkH69ZqcstinTYaH/view?usp=sharing