Wow! that sounds interesting. you want to make hybrid one(both combustion and electric) or completely electric?. Conversion to electric completely involves removing of combustion engine and use torque metering devices in all the four wheels which will be run by a electric battery. These torque metering devices will have electric motors which provide required traction for wheel. Each device provides different torque to different wheels based on road conditions and help in maintaining optimum tire grip.

If you want to make a off road vehicle,you must have a much rigid chassis than your Alfa romeo one I guess. Because Alfa romeo is a monocoque chassis which is integral with the body and cannot withstand higher forces from off road conditions.

monocoque chassis.

Rigid chassis: