The turbo drain is primarily sealed by the O-ring. The grommet is basically a back-up seal. There have been folks that goobered a bunch of RTV on there but it's so darn easy to fix, I can't see the reasoning.

There has been several write-ups on how to do this but most make it entirely too difficult. It requires no excessive force and dropping the pan is unnecessary.
1)Unbolt the upper tube from the turbo.
2)Push the top tube down to minimize the length.
3)Tilt the tube out towards the left wheel and remove the top section.
4)Tie a section of rope in a clove-hitch around the lower section and wrap the other end around a large pry bar, using the manifold for leverage.
When re-installing, use assembly lube or silicone grease and install the grommet on the lower tube about 2-3 inches above the end.
5)Install the O-rings and insert the lower tube.
6)Tilt the lower tube and install the upper tube, pushing the two sections together.
7)Tilt it into place and bolt the upper tube to the turbo.
8)Last, slide the grommet down the lower tube and gently pull/push into place with bent nose pliers. Use plenty of lube to keep from damaging the grommet.

I've changed mine out in about 15 minutes.

__________________
Sam

84 300SD 350K+ miles ( Blue Belle )