Here is a pic of the difference in the bolt angle that is the opposite of the situation you would have if you use a later intake on your 65 motor. This pic is of an Edelbrock D4B sitting on a 273 with later model 302 heads. If you used, say, and Edelbrock Performer on your 65 heads, the gap under the bolt head would be at the bottom instead of the top. I've read on here where guys have used what's called wedge washers or angle washers to equalize the gap, but have no clue where you could buy some.
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