To install the upper gasket. First install the gasket on the upper tube, not the turbo. Use Permatex High Tack. It sticks the gasket to the upper tube and will hold it while you get the tube in position and the 2 mounting bolts threaded. Then use a long extension with a spring loaded universal to tighten the bolts. I did the job from below the car.
This worked both times that I did it on the 82 300TD.

Dave

__________________
1970 220D, owned 1980-1990
1980 240D, owned 1990-1992
1982 300TD, owned 1992-1993
1986 300SDL, owned 1993-2004
1999 E300, owned 1999-2003
1982 300TD, 213,880mi, owned since Nov 18, 1991- Aug 4, 2010 SOLD
1988 560SL, 100,000mi, owned since 1995
1965 Mustang Fastback Mileage Unknown(My sons)
1983 240D, 176,000mi (My daughers) owned since 2004
2007 Honda Accord EX-L I4 auto, the new daily driver
1985 300D 264,000mi Son's new daily driver.(sold)
2008 Hyundai Tiberon. Daughters new car