when i did it, i was a lvl 65 full prot spec, and i had my 70 fire mage come with. it was a joke. he killed them all in two shots.
given that, i would think its safe to say you can kill them all at 67 aoe style as a full prot while your priest friend kept you up. and did some damage on the side.
the mobs, if i remember correctly will be lvl 60. and they will all be scaled down a bit.
they should be green to your preist friend so he should be able to do really good damage to them also.