Complete characters and heads

[Vkathrynr]

Hi,

I'm having trouble with attaching modeled heads to complete characters. The complete character/head seems to look fine from the front (and even partially around the side). But, when I look at the avatar from the back, the neck looks like it extends part way down the back. Basically the head seems to sit too far back on the avatar's neck bone.

Is there a simple fix for this?

Thanks,
Kathryn