Edelbrock carb I.D.
Edelbrock says you should run the steel plate when using that carb on a Performer manifold.
Jegs has them for 6 bucks - #555-1542
Or you can use the Edelbrock # 2732
It really does help with the heat soak, as well as spreading the sealing load.
Go ahead & mount the carb without it if you need to, but pick one up as soon as you can.
B.