Sam is correct....Colvin's book doesn't even list the L78 application for 1968 Camaro or Chevelle...but the 814 is the correct part number....an August dated unit might be a little early for a Feb car...but I had an original 837 with a June 69 date on a Feb/70 L78 car....these were made in batches so there won't be a lot of different dates to choose from. Maybe someone else who has a 68 hipo car can give you some guidelines on dates they have. Our 68 L78 Nova is a July car with a May dated 814.
wilma