We should not forget this is the same company that had an amazing lead on everyone in the electric car market 3 decades ago with the EV1. See "Who Killed the Electric Car [0]
replacing a gas engine with an electric motor and installing a battery pack is not hard. The EV1 was a pretty bad car. The real secret sauce of modern electric cars is cheap Lithium Ion battery packs.
That and making them look like normal cars not futuristic golf carts.
The EV1 predated the Roadster by a decade. Had GM been improving the EV1 for those 10 years, including Lithium Ion batteries, GM would have been far ahead of everyone . . . had they just kept going with a technology that was inevitable. Where would Cruse be today had they continued with this new technology that is inevitable?