problem with resto. can anyone help?

[Hesford]

My kx500 1983 im starting to restore has the wrong serial numbers!!
Engine and frame BOTH say: 1983  15002970. which i know is completely wrong and have been made up.
  Does anyone know how else i can identify it?
  It is air cooled so that narrows it down, definatly a 500.
  Has anodised gold swingarm.(1983s do dont they?)
  On headstock, (opposite side to serial number) it says 'MADE IN JAPAN KHI' and this is original so it must be a kawasaki frame.
 
 There are other markings on crank cases and top end. does anyone know what these relate to?:
  On top of the barrel on exhaust side theres a 'B' stamped in.
  On crank casing under where it says 'MADE IN JAPAN' theres a 'K' in a circle with a '1' next to it.
  On cylinder head theres an 'A' in a circle with a 1 next to it.

does anyone know of any other identifying marks on both engine and frame or anyway of me dating the bike.
  I need to find out how much of a kx500 1983 i really have before i get in any further.
    Any help would be appreciated, thanks Chris