The tank, seat, and faring for my RD400 project will one day be polished aluminum. I'll also be making side covers to fit the new rear end. I'm thinking, I'll just make the side covers out of plastic for now. The tank and seat have a bad fit up so my plan is to make an oil bag for the two stroke oil to fit the gap. The cast tank will have the oil tank inside. I'll also be taking a few inches out of its width to show some engine fins, and to make it fit up to the seat better.