Originally Posted by
CGOffroad
The original design of the housing on the forward side of the internal wall is the oil tank. Aft of the wall was the overflow catch basin. If you have holes drilled through the interior wall, your car has been modified to increase the quantity of oil held in the oil tank. Then, an external catch can is needed. The holes on top and to the aft of the swirl pot were the overflows from swirl pot and into catch basin. It sounds to me like your bell housing has been modified.