For your information, I have a 400 block with a Holley Street Dominator manifold, 750 DP, and a 1/4 inch heat insulating spacer under the carb. The stock air cleaner fit, but it was so close it was rattling on the hood bracing when the engine was running. I used clay and determined the clearance. I ended up trimming the bracing a little, since my car is far from stock. As you can see, the issues are at the front right corner and at the very back.
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