Thank you for your quick reply.
Can I ask why you are using diodes? To avoid peak currents? Wouldn't 1N4001 diodes be okay (I have a bunch of these...)
I see a capacitor, what would be the value? 100UF would be fine or do I need higher value? Do you use it to prevent a voltage drop at the time the voltage switching occurs?
I disabled BOD in the pics, should I expect a reset anyway if the voltage drops a little?

Thanks mister_e