The serial is 502 46560 887408. The bike is complete, I may fix it up as a cruiser, or completely restore it depending on parts availability, but for now I'm trying to find out the basics. I can see a bracket on the head tube, perhaps it once had a tank?
for Sears the first 3 digits are a manufacturers code.
502 is for Murray Ohio as the manufacturer.
4656 is the model number. It's also the order number in the catalog. There are books for sale on Ebay that show the bicycle pages from the Sears catalogs that cover Elgin, JC Higgins, and Sears bikes from the early 30's through the mid 60's. Each page tells the year from which the pages are taken. Match the number on the bike to the cataolg number and you can figure out the year and style. The 502 is Murray Bicycle's code for the bikes they built for Sears. The last six numbers are the bikes individual unique serial number.