fuel tank "gasket"

Hey List,

I am ready to put the tank back in the midget and see that there is a paper 
shim or
"gasket" stuck to the bottom of the boot around the edge where the tank goes. 
It is
necessary to replace this? I really don't have anything of similar quality and 
was
thinking that just some duct tape squished in there would do the trick. I also 
installing
a panhard bar if that would make a difference. I take it the "gasket" is to 
keep down
vibrations or something like that.

Thanks