I've got a 68 L78 M22 & 4.56 with NOM and all the paper docs. I bought it from the original owning family in the same town the car was delivered. Anyone remember it at Wayne Meinert's eighth mile track in St. Louis AKA Gateway? OK, so it doesn't have the original block but it also has some other qualities I appreciate and value in a car. Those factors just dont seem to add value like those tiny factory digits
I paid 35K for the car a few years ago. I knew at the time it was a premium but I wanted it so it did'nt matter too much. I guess with current economics it would be worth about the same now as then? Hope that helps with the original question some.