The eddy afb 1406 is one of the worst carbs ever built
In the 60 Chrysler did not use the AFB , the use the superior AVS which at least has an adjustable spring loaded secondary door not a non adjustable weighted door .
I have struggled to set up numerous 1406 for customer with Zero success , the fist thing I do is set the float level as it is always wrong & drill ho;es in the counter weight as it is always to heavy & slow to open . if you have any ca, at all you cannot adjust the air bleeds so it will respond without a lag , they one make 3 squirters small medium & large , they come with medium & often you still have a bog even with the large squirter so then you have to drill carefully to get more pump shot .
later Chrysler used the 800 cfm Thermoquad on the 340
Literally any carb will perform better in my experience you are just throwing you $$ away , if I cannot trade them I toss them out & refuse to install them on any car for a customer .