The V is Flint 11 is Nov and 13 day so Nov 13th I get the HF letters to be:
1965 HF 327 h/p 300 4 Vette
1966 HF 327 Powerglide, A.I.R. 275 4 full size
1969 HF 350 Powerglide 275 2 A F X
1978 HF 350 LM1 170 4 Firebird
The mortec casting number reads:
3914678....302.....68....2...Z-28 Camaro
3914678....327.....68....2
3914678....350.....68....2
