Jerry,
The combination of stretching, massaging, and the passage of time should help you see some improvement. (Coincidentally, it is now 16 years to the day since I had a partial glossectomy and neck dissection.) The tightness and numbness around my scar were noticeable for quite awhile, but eventually the scar tissue softened up, the nerves regenerated, and that entire area pretty much reverted to "normal" -- bit by bit.
Cathy