M166 is a December 16 1966 casting built for a 67 model year. YJ is a 250 HP 326. 9786339 is also a 326 block as cast for 1967. The D4N is the day shift or night shift casting shift. The 16 can be either be 1968 or 1969 big valve #16 heads or 1970 small valve 16 heads. The 400 stamped in heads is correct. They are either 68/69 hipo heads or 70 lopo big car.
Si Vis Pacem Parabellum
1967 Starlight black PMD Engineering 400 Auto 1968 Alpine Blue 400 4 speed 1968 Verdoro Green 400 HO 4 speed 2013 1LE 2SS/RS Inferno Orange Camaro.
