Joined: Nov 2016
You can probably make your existing carb work fine, but if you're burning to get something better, don't grab a Holley. Get a 600 CFM Summit M-series carburetor. You'll pick up several MPG and a whole lot of power down low, thanks to the better atomization from the annular boosters. It'll run smoother and make less pollution. Top end will be similar to the others, but why spend more for less? They're inexpensive too.
As for a heat insulator, Edelbrock carbs are pretty bad about boiling over. Most carbs are, with modern gas, and the high alcohol content. Using a phenolic spacer is best if you have the room for one, but a 'thick' gasket is all right. Since you are talking about taking the carb off, you really should replace that gasket anyway, and I wouldn't spend the money for another - so long as you have something there to help insulate.
Out of the many suggestions you've gotten so far, choke operation is the big one I'd look at. Best wishes!
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