You can hack it into parts then re-assemble into a new symbol. At one point @Alaskan_Son had done a video on using the delete surface tool. Basically I set the camera to clip surfaces within 0.1 in, hide everything except the symbol then open the symbol and set the smoothing angle high (120-180) Setting the smoothing angle that way makes it so more of a part is selected at one time when you use the delete surface tool. For instance, RAS waste basket- using delete surface too