I looked at the bike really closely, and there is no four-digit number on the badge anywhere. The badge says, Schwinn approved Taiwan, and there is a sticker at the bottom of the center tube that says "Product of Taiwan R.O.C.". The only four-digit number I found on the bike anywhere is "5583" and it's on the front of the bike, right behind the brakes (not on the brakes though). From my previous research, someone told me that this means the bike was made in Feb. 1983. Although I am not sure now.
I took a picture of the numbers. Please Advise.