Even if you would drive your own vehicle to the shop, this is a case where I wouldn't recommend that to a friend. If it overheats and costs him a new engine, you could be easy to blame.
Off topic--I'll file this information away with my Chevy 5.3 that locates knock sensors under the intake manifold and the Vibe/Matrix/Corolla 1.8 that puts the PCV valve behind the intake. I notice the improved manifold has a plastic nipple on the bottom left, where the stock one is brass.