adapter plate

i have the stock thermoquad intake manifold and just bought the street demon 750. The primaries on the carb are bigger than on the manifold 1/8th of an inch. i need either an adapter plate or a spacer to make it work. Have any of you had this problem, and how did you fix it? What spacer or adapter plate do i need?( i have about an inch of room)

Thanks,
Zach