 The no serial Greco guitars made by Tokai have square shaped routing holes at the bottom of the pickup cavities whereas the no serial Greco guitars made by Cor-Tek (Cort) have thinner rectangle shaped routing holes at the bottom of the pickup cavities.Kanda Shokai stopped using the open book headstock design on Greco Gibson replica models around the early 1990s and then concentrated on their other model lines and Fender Japan.Atlansia have supplied body and neck parts for Greco models as well.