From what I see, I don't think you will be able to put a spacer of any type under the carb.
What size vacuum line is it running from the front of the carb to the firewall? That fitting position on the intake was the same vacuum source as used on the 1960/ 292 PCV System.
That may be your out w/o changing the appearance too much.
Beautiful detail BTW. Is it a restoration or survivor?
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- MULTI-VEHICLE SYNTHETIC TRANSMISSION FLUID -
Multi-vehicle transmission fluids are becoming more and more popular in the marketplace. Oil marketers design these fluids for a wide range of automatic transmission types. While they are not licensed by any specific auto manufacturer ... ??? ... enough said ...
DIAGNOSED CDO - (OCD In Correct Alphabetical Order)