would this date code on the engine be consistent with the date the car was built?
06A tag code (1st week of june) engine block #3914678 dated D-22-8 same on the heads (april 22 1968) code is MS, so somewhere between 5 to 6 weeks before the build date of the car, transmission is second week of may 1968. 350/295hp SS engine

couldnt get any better .........4-6 weeks is a good date

Casting dates are not relevant. What's the complete engine code? xxxxxMS?