You can change the hex hubs to those from the buggy or ST. They are 12mm so finding touring car foams is easy.
Steering bellcrank bushings are terrible but you can replace them with 4x7x2.5mm bearings (you need 4).
Also, from trial and error, I found that traxxas latrax teton (1/18) driveshafts part# 7650 or the hot racing version are interchangeable for the SC or buggy. Duratrax driveshafts are getting really hard to find and are expensive. Hope this helps .