[Mr70]

That's a 396 block used in various applications throughout 1969 like Passenger-Chevelle-Camaro-Nova.
It came in 265HP-325HP-350HP-375HP ratings.
Came with either 2 bolt & 4 bolt mains.4 bolt being the 375HP only.
Most of these blocks had the casting date down around the passenger side freeze plug,but some had it atop the passenger side bellhousing flange during a brief window of production.

CE stands for Chevrolet Engine which means it was a warranty replacement over the original.
The very first digit after CE will stand for the year it was replaced..i.e. 0 for 1970 in your ? area.
The numbers following it is the sequence number,i.e. 67663rd unit produced for service at the Tonawanda plant.
No way to say for certain what vehicle it came in by the numbers you posted.