Although I have owned my D since 1986, this will be the first time I have corresponded to the group. My serial number or VIN #is SCEDT26T7DD016111. When D owners write back and forth they often sign off with their VIN #, generally 4 or 5 digits. I'm guessing then that my VIN or production number is 16111. The D is a 1983 - How do you determine when the car was produced and more importantly what up-grades should I perform to the D. Thanks