The Peugeot HYBRID4 first generation (the one with the tiniest 1,1kWh NiMh battery) would make a good case for an "up-fit" / "hack" with a larger and higher voltage battery.
From what I gather, the rear diff has a Bosch SMG180/120 which would be good for up to 80kW and 200Nm at the motor.
The inverter which seems to be another Bosch item : INVCON 2.3 seems to be able to accept 400V right off the bat and the necessary current for the 200Nm.
However, the limiting factor is probably that 200V / 1,1kWh NiMh battery which is probably limiting in terms of power output as well as top speed (with the 200V).
Given all that, has any of you been able to make :
- The motor/inverter run on it's own via the CANbus
- The rest of the vehicle believe that the Battery/Inverter/Motor is correctly behaving in order to keep it in Electric mode