Classic Wow

I'm having a bit of struggle tanking (prot paladin) Vek'linash. I'm able to hold threat on him fine, but unbalancing strike (-100 defense) rocks me pretty hard, since I keep getting scarabs on me, which eats up all my HS charges and I'm pretty sure that's pushing me into crittable range as well as crushable.

I've taken consecrate off my bars and de-runed HotR for exorcism, but I keep getting the scarabs too, and then get rocked down to 20% health.

Any advice? I've stacked as much +def as I can and am using Greater Stoneshields and armour elixirs as well as the usual suite of ALL THE CONSUMABLES.