Unless I'm missing something, it does not seem possible to reach 102.4% unless you have literally every piece of wrath block rating gear as well jewelcrafting and blacksmithing. When my Armory updates you'll see I'm coming in at 101.61%. If I backpedal a couple enchants to Burning Crusade w/ Defense on bracers and Block Rating on shield, I don't think that'll quite cover the gap.
Let me know if I'm missing something. (If Armory doesn't show Jewelcrafting then it hasn't updated)