turbo noise or exhaust leak?

[JimT]

A few questions:

* Does anyone know the thread size for the exhaust pressure tube on the elbow of the exhaust manifold? The threads inside are visibly good but full of rust/dirt/debris causing the threads on the pressure tube to partially strip/flatten the final 30% in. All my taps are imperial and wouldn't work on this application anyway.

* One of the studs on the turbo mounting also snapped on disassembly. I haven't tried removing it yet and there's still about half of the upper threads remaining. Any tips / tricks / recommendations to aid in removal?