first of all load the gp3 carshape and save it as ctf file on your hd, then close the car editor and open it again. Configure it for gp3 2000 and after this, import the carshape from gp3 2000 exe. Now you can load the ctf file and insert it in the carshape. At least save the new carshape and you can use it for gp3 2000