hello, I'm brand new to the group and have a question. I recently purchased a World Sport (garage find) but the serial number seems in an odd place. The number is below the crank and starts with a GC. I know it is from Giant but there is also no serial number or date code on the right rear axel hanger. It seems strange but I cannot find any information on the web as to this specific location. Does anyone know anything about Schwinn/Giant serial numbers that could help me out??? Thanks!!