That might not be a bad business to be in. There will be a combination of carrot/stick approaches to get ICEs off the road. That could include outright bans on ICEs in large cities, probably starting in Europe/Asia first, but eventually coming to North America. The end result of this could be vehicles with perfectly sound bodies which the drivers still like, but in need of being retrofitted with an electric drive train. Anyone who can produce drop-in electric drive trains for a reasonable cost might be in a good place in the next few years. Granted, David's goal here seems to be more power/speed than the current offerings, but in general I see this as a major growth industry. Think something along the lines where you could take out the engine/transmission, bolt in the electric motor and associated controller, which in turn interfaces to the vehicle's throttle/brake wiring. Put the batteries wherever they fit, connect to the controller, and you're done. There would probably also need to be a small screen in the car which tells you what the motor and batteries are doing. Not as elegant or efficient as a purpose-built electric car, but to the driver it should feel more or less the same. Probably smoother without the vibrations and jerky characteristics of an ICE.I LOL'd.
Wait a minute! Maybe this is DD's secret upcoming venture he's looking into. "Drop in electric drivetrains."