I have a list that I found years ago online, but have no knowledge of how accurate it is, take it for what it is worth, but it lists some serial numbers, and I don't know if they are the start, end or individual machine. Anyhow:
Feb 68 126125 First Production Machine
Mar 69 131180 Fastback
Mar 69 131257 S with Camshaft Points
Sep 69 133668 Fastback with camshaft points
Sep 69 134108 First Wolverhampton engines (P-suffix)
Mar 70 135140 Roadster
Jun 70 135088 Last S
Sep 70 ?????? Fastback MK II
My 69 S is s/n 132030 and does agree somewhat with this list. I am pretty sure that they made series of S and Fastback and Roadster within these serial numbers, and there seems to be no accounting for which are which.
Dave
69S