Load up on any fire protection spells you got, then use the "peek-a-boo" technique. Send your thief ahead to scout for traps, when he/she runs into a kobold, run away back to the party. Some kobolds will follow, some will not. Seems like though the kobolds only have so many shots, then they run out of arrows and run towards you, easy prey then. When you get to end with the mage and the golems, just toss in some skeletons ahead of you to help take them out.
Hard level no doubt. I had to move my NPCs one at a time, and save every time I killed anything, inched along, got through it with patience
Whew!