In situation as above, you could define an offset for vector, then rotate it with the object and after all that add to the results the origin position of the model (your 3d model).
It should be something like this:
Code:
vec_set(temp_vec.x, vector(100, 0, 20)); // values taken from your example
vec_rotate(temp_vec.x, my.pan); // my.pan - here is all angles of your 3d model
vec_add(temp_vec.x, my.x); // my.x - is the position of your 3d model
