They should be interchangeable. They (the gen 1 gyro and the gen 2 internal inertial sensor) do default to returning values that change in the opposite rotational direction, but worse case you would have to change the sign on returned angles.
Anyway, to answer your original question, it probably doesn’t matter that much, but placing the gyro at center of rotation of the robot is probably the best you can do. Error and drift tend to be caused by issues somewhat out of your control, vibration from motors, things like that. For VRC moving the gyro away from motors and mounting using rubber couplers would help, but you don’t have that option.