The large flex disk with voids around the bolt sleeves goes in the front. Rears don't usually fail very often, but hey.

You will want to pull engine and transmission as a unit to get to the seal unless you have a hoist, it's way too much hassle on jack stands. You will have to get the rear of the engine tilted down far enough to reach the top bell housing bolts going back in, and without the tranny to drag it down, it's tough. Probably takes less time to yank the whole shebang, split it, replace seal, bolt up, and reinstall than it will to get the bell housing bolts back in.

Make sure you don't have a head gasket leak before pulling the rear seal.....

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!