[Britwrench]

Assuming you are refering the Intermediate shaft housing at the flywheel end of the case, this is the part that leaks oil into the clutch housing.

The IMS housing/seal assembly was updated, Porsche sells it and most shops replace it when changing RMS as well as installing the updated case bolts.

You need the intermediate shaft housing 996 105 017 02 (up to engine number 661 14164) , updated case bolts 4 x 999 385 0004 01 (long) 3 x 900 385 275 09 (short), the tensioner crush washers, updated rear main seal (factory part only), eight flywheel bolts and six clutch pressure plate bolts.

If the clutch and flywheel require replacing, there are also updated release lever parts to be installed.