Why wouldn't you put it in one of the exhaust manifolds regardless of whether your turbo or not? That way, you get the hottest reading possible, which takes some of the guesswork out of how much you think its cooling. My understanding is that the engine will melt before the turbo will, so the EGT gauge is protecting the engine primarily and turbo by default. I'm getting ready to do this myself, and was planning on plugging the port in my Banks turbo (which is a good 3-4' of pipe away from my exhaust manifolds) and drilling and tapping between cylinders 6 and 8, which fire one right after the other if my understanding is correct. Them being located back driver side is a plus because that's where all my wires run through the firewall.