PaulS:
Surely at this point it's time to move over to visual tracking? I can't imagine a 2 GPS system tracking a moving target with a laser. There's just too many variables...
Seems like a lot of people missed:
Base station will have servo with laser pointer (for test purposes only now) to aim at moving object.
I assumed the laser pointer was to visually check the tracking of the base station and that what ever the project was intended for, it still requires the same amount of accuracy.