I don't know if it came with all 409's but it included different springs, different shocks and an additional upper control arm on the differential. (3 arms on the diff vs 4 arms on the diff)
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars (now converted to a "factory" 4 speed)