Interesting that the thread has turned to electric cars.
I am amazed that a company has not produced an electric hybrid kit for classic cars.
Classicelectriccars do conversions using tesla batteries and an electric motor, but it is certainly not an accepted and wide spread option. It would give you extra low down torque and can be used in cities.
35hp is all that's needed as that got my old Series 2 4/4 around. Start up your 4, 6 or 8 out of town and give a nice big green smile.
When you see the value of the cars in Classic and Sports car magazine we are talking billions of pounds worth of potential obsolescence. Or perhaps they are all just for driving around your private estate and for the heated glass showroom.