Spitfire R6779, shot down 8th October 1940

Can anyone help with a code letter for Spitfire R6779, flown by P/O George Corbett in which he was shot down, probably by Adolf Galland, & killed on 8th Oct 40 over Sheppy?

I know the 66 squadron code was LZ but what was the individual aircraft letter?

He took off at 08.30 on the morning of Oct 08/40 as Blue 2 with Bobby Oxspring (R6800 LZ-N) and P.O. Cooke (X4421 LZ-?) when he was shotdown at about 09.20 and killed.

Thanks

Jeremy Wright

NB I have the oil filler cap to this Spitfire Mk1 collected by my father Rev Aubrey Wright on the day of the crash at Bayford Marshes. I would like to display it with a model of R6779