if its the problem i think your having. When you start the nuts on the studs lift the turbo off the header an inch or so, so that only a little bit of the the stud comes through. the nuts should spin when they're flat against the exhaust housing flange.
bump.
just bought a bag of 10 from the local Chevy dealer. $1.70 something each.
Thanx Jimmy for the part #
McMaster-Carr should have them
Part # 91028A667
Metric JIS Hex Nut 18-8 Stainless Steel, M10 Screw Size, 1.25mm Pitch, packs of 5 $6.09
They have a 14mm head