Drt float chamber cover and spacer

I have fitted a drt float chamber cover and a 2mm spacer to negate any chance of the float chamber running dry at full throttle. i am a bit confused as with the kit I had a metal 'gasket'for the cover. i didnt fit it but just fitted a paper gasket. i have now read that i should fit 2 x gaskets with the metal one. (i take it one either side of the metal one. can ayone advise please.

Also is there a need for some sort of gasket with the spacerfor the float chamber as its metal on metal../