1995 Tacoma 2.7L fuel filter seals

I am in a quandary regarding the fuel hose/filter seals. I've been fighting a fuel filter leak after replacing it and when I disconnected and removed the filter I discovered that some of the seals/washers were made of low carbon steel. that does not sound right to me. aren't they usually made from aluminum or copper?

Second question regarding seals: In a top end gasket set I bought, it included new seals and one of them is irregular shaped, it has a small rectangular hole adjacent to the ID/OD. Does this seal go in a particular place on the fuel line connections?

 

The FSM shows that gasket between the line from the tank and the filter with the rectangular side facing up on the installed filter. The circular gasket is on the outside between the banjo bolt and fuel line. I'm not sure what it's for. I thought maybe it makes it easier to hold in position without dropping it, but it's only on the one side.

The Toyota filter comes with the gaskets.

 

Okay, thank you