GT6 Chassis number

[Thomas Carney <tcarney@concentric.net>]

  I have a question about my 69 GT6. I was recently looking 
at a book with the different chassis numbers for GT6's.  I 
noticed that my GT6 number starts with FC.  Correct me if I 
am wrong but isn't that the suffix for an early Spitfire 
chassis.  Plus my chassis number doesn't seem to fit within 
the production numbers.  It is FC136336.  Can someone help 
me identify this chassis?
Tom