[madderscience]

+ 1 on golf cart drivetrain - do some research and see which ones have the best power/gearing options for a street legal vehicle. get one that was designed for 48V or higher, and run 72V minimum battery (meaning upgraded charger and controller, the motor will probably be fine) For batteries, get 10-12 leaf modules (or 20-24, paralleled), aforementioned volt module, or a bank of 24 100ah LiFePO4's. Don't bother with lead.

Another approach to the drivetrain might be an ATV rear axle unit, with engine replaced by electric motor.