If you are racing in Canada the plate goes behind the phenolic spacer( the black spacer behind the carb ) and you use the D shaped gasket on both sides of the plate. In the US the plate goes in front of the spacer rite behind the carb and you would use two of the gaskets that normally go there. That would be the gasket with the hole in the middle and small vent hole at the side. Make sure the vent hole faces up and to the left when looking at the gasket.
Bruce