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That manifold is for an EGR application, and requires an EGR spacer to be used on it, or have the hole otherwise blocked off. Major vacuum leak will occur if you don't.
Thanks do some carbs use it because it seems to be outside of mine
I'm not exactly sure what you're asking. The original application stock used an Exhaust Gas Recirculation valve (EGR) which bolts to the carb spacer. To pass emissions regulations, Edelbrock offers a replication of the system so you can retain the EGR setup. It will all work with the stock 2V carb. The big 1407 Edelbrock carb won't need the EGR, so if you can figure out how to delete the whole mess, you can. If you're going to use that intake manifold with the hole you marked, you just need to make or find a flat plate to cover the hole, with gaskets, of course, then bolt your carb on to be good to go. A typical 4 hole spacer may not have enough meat on the side to seal the hole properly, and if it doesn't, see my note in my post above.
Edit, upon further pondering, it won't be a vacuum leak, but an exhaust leak. That hole runs directly to the exhaust crossover. The valve allows the exhaust gas to be put into the intake stream through the spacer. Either way, the hole must be blocked off if you're not using an EGR spacer.