Metal slivers in the oil pan usually would be the rod bearings are worn. Number 2 is the normal one to go first. It could also be the main bearings but cross your fingers
If the car ever had the oil cooler gaskets go bad and the coolant mixed with the oil, this mixture will eat rod bearings. Porsche wants the rod bearings changed if this happens.
Search for rod bearing failure. Here is a link from member TexasBlake....
Rod Bearings - Porsche 951 - www.texasblake.com
As you can see it is a time consuming but doable job.
GL
John_AZ