Hi Ian,
Leccy fan only. It's a very tight squeeze with a Kenlowe, which still works fine. Even changing the fan belt is chalIenging! I would wary about replacing it with something newer, without seeing it fitted to a Vit. How many times have you been told ' oh yes it will fit', when clearly it won't! I still don't think Revotec have produced a proper kit ( with mounts) to fit a Vit yet. I've always had a manual o'ride switch, which has proved useful.
Gav