edelbrock performer 318 360 and an adapter plate problem

Performer 318/360 Intake Manifold for Small-Block Chrysler, LA Series Engines


yes it looks flat..........i just came across this though.....it seems they have their own plate to use for squarebore carbs.
it looks like i dont have to use the 1 inch thick adapter.
i took an old edelbrock off of it and it had this plate under it.
the edelbrock had slightly larger secondaries so i thought it was a spreadbore carb but i guess its not.
ill try it again with just the plate and report back after this weekend.