I picked up a Gran Turismo a few months back, and I don't know anything about it. The serial number is L970773 . I did some searching to see what I could find about serial identification, so I hope the number helps.
It has Suntour Seven derailleurs and Dia Compe brakes. It's a 15-speed.
I'd like to know the model year and frame construction if at all possible. The sticker for the frame material is nowhere to be found.
I'll try and put a couple of pictures up.