Jeb
Yes the sprocket would have to be turned from the inside.
So my guess is that this sprocket could be driven by sprocket on the crankshaft snout were the
oil slinger would be or just maybe a crankshaft gear for a Gear Drive timing system.
The sprocket for the external pump is located inside and right at the front of the
oil pan and would fit just inside the timing chain cover.
There is no input or output port on the pan, these ports are located on the external pump that is located at the front of the
oil pan, slightly behind and below the balancer.
No I have not fit the pan on my 427 FE but the pan is definitely for an FE.
To see the pic of the dry sump click on the link below:
Ken