Hello, friend!
Don't forget to add Heavy Borean Armor Kit to gloves (my favorite since I don't pick Engi on tanks) and +18 Sta to Shield (TBC enchant).
Also,
this is the build which I use for gearing up in dungeons. I put the last 2 TPs into Imp Spell Reflection, but there are many options, really. Glyph of Cleave is also very nice for this spec.
Now to my question, you mentioned it was possible to reach unhittable in WotLK and I am interested in it for the sake of soloing vanilla content (Lifeward does wonders with Thunder Clap). Could you provide more info regarding this?