A 4wd M03 would be very cool.But it would be almost quite impossible .The rear out drives would be easy get the Get a front end 4wd diff and drill the holes in the rear of the chassis to take flanged bearing that will fit over the out drive shaft.Now the hard part it would have to be a two belt drive system .you could run a s gear out the side of the motor .down to a another gear with a shaft to that has gear that fit inside just in front of the were the body is bolted together.Then a belt to the diff. Sound like a lot of work to me
Plus I like the way the rear end slides around like most cars with front wheel drive.More true to life there really is not many 4wd car out there.I have not seen a 4wd Ford Focus,Hyundai Excel yet except on the WRC.