You should get an SC10RS, sell the receiver and tx on ebay for whatever you can get for it and you'll have a kick ass sc truck that comes with a gear diff already installed right out of the box to go along with your other car.
Or you can keep the stock radio equipment if you want. Its your choice. Either way you'll end up with the best sc truck out there IMHO. AE has been doing 2wd race trucks for longer than anyone else in the biz.