I took the rear aluminum hub carrier off and put on a plastic one.
The front aluminum hub carrier is fine because you have extra tuning holes.
The one thing that's different from the regular 501 and the wce is the pulleys, and the body, and the included swaybars.
I wrote tamiya on facebook about the new car coming out, and nothing was said. So I dont know about the new car.
I dont think the 511 was discontinued I just think tamiya is out of stock.