I have been looking at the standard battery location on the Viento (top of bulkhead, passenger side) and thought I could use the space for other things.
I was thinking of fitting the battery low down in the engine bay in front of the passengers footwell, supported on the chassis rails in a protective box. I can secure it aginst the footwell. It could be installed from underneath by jacking up the car a few inches. It would keep the centre of gravity low and i have plenty of space. Am i missing something obvious or has anybody else done this?

Took this photo at luego workshop two years ago.. Its a left hand drive viento. The battery seems ( DONT kNOW FOR SURE ) to be located in a conpartment in the passenger footwell - plenty of space!
Rescued attachment bmw3.jpg