2bbl spacers??

What kind of carb to you plan on using for your setup? If Vapor lock is your worry, try using a Phenolic spacer. This material can be bought and made into your own spacer, or you can try to find pre-made ones. This spacer does not supplement a carburetor gasket, and should be used in conjunction with a base gasket.

Use longer bolts to accommodate the spacer, and adjust kick-down linkage if necessary.

Check out Aggressive Ted's setup and see his neat application of an aluminum heat deflector for some ideas.