Very rare GS 3180 ! early carved logo index , first case back medallion early type , single piece 12 index , under 6 position write GSJ14H156, sn no 0015264 traced back to oct. 1960 5264 units n mountain hands ! Movement no 607018 also match w the period ( 60 stands for 1960 n 7018 about oct ) . Price firmed . W rare GS buckle. Overhaul recently
https://thegrandseikoguy.com/2018/06/04/a-guide-to-the-grand-seiko-first-dial-variations/