IBM serial number query

Someone contacted me and said they have an IBM PC that he was told was the 35th off the assembly line. The serial number he gave me off the unit is 0205544. He also gave me a number he found inside the chassic which is IBM1800841. He said the motherboard has been upgraded to 64K. I don't know if he meant it was upgraded to the 64-256K motherboard or if the RAM sockets on the original 16-64K motherboard were populated. Can anyone shed any light on the serial number(s)? Sellam Ismail Vintage Computer Festival ------------------------------------------------------------------------------ International Man of Intrigue and Danger http://www.vintage.org [ Old computing resources for business || Buy/Sell/Trade Vintage Computers ] [ and academia at www.VintageTech.com || at http://marketplace.vintage.org ]