How important is the heat shield that covers the exhaust manifold? Some how I have seemed to have lost a few of the little bolts that hold them on, I think there are 4 or 5 of them, and well I just have one... AndI tried buying new ones and I cannot seem to find any around here...

I am going to keep the heat shields that vover the turbo and downpipe area, to keep the heat away from the intake....