I rebuilt the top half of my engine (head job and turbos) with the engine in the car twice and you have to figure out so many little tricks and make sure every thing is done in a certain order. I didnt have access to anything to pull my engine or a garage to store it or work in so thats why I did what I did. I was all done outside in the driveway and the parts were kept in a small shed (very small).
I dont see how you could properly torque the lower nuts on the mani's doing this in the car as well. Or the inner nuts that hold the turbos to the mani's but hey have fun.
"torque gets you off the line...& hp gets you over the line." - TTKeeper