Align neck body to head geometry I did some editing of the head so it no longer fits properly to the body. How do I match the body neck mesh edge to match the head neck edge perfectly? 

I know I can connect them and then detach but I already have vertex groups and face keys for the head, is there a more passive way to align the mesh?
1- Enable the Snapping Tool clicking the magnet on the 3D view bar. 
2- Next to the magnet icon hit the icon next to it to select snap to what> Select 
Verex.
3- Select a vertex along the neck edge. 
4- Move cursor close to its desired destination.
5- Hit G, then ENTER when in snapped position. 

Note: Transform manipulators doesn't work well with the magnet.