The 600 series was a consistently popular guitar, and had a few interesting deviations from the main line over the years. One variation was a lovely all-mahogany model with a faux tortoise pickguard, another was an all-black 1217 towards the very end of the model run, and one was an off-the-wall Made In Italy EKO-built arched-back bolt-neck that was only listed in the '65 Wish Book. The line well and truly came to an end by 1972, ending a nearly thirty year run.  I'd like to see a graph of 600 Series sales vs. 604 sales; wonder who'd win?