best “square flange” carb for millage?

Ok so I have been driving my duster to work every day. I live in a area that I can't park a car outside so unless I am willing to sell the duster {NOT!} I will have to keep driving it. I have a 60 mile round trip and need to optimize my millage.
Current configuration is
360+.030" 8.5-1 comp
"J" heads "hughes stage #2 ported (68cc cambers)
340 grind cam
wiend dualplane intake
650 holley dp
cheap headers-2 1/2" duals
msd dist +6al box 36deg total adv all in by 2000rpm
4sp w/2.76 open rear
255/60/15 rear tires
I think that the holley dp is just not a very good "millage" carb. I have adjusted the pump linkage so that they are less "sensitive" and am running as lean as I can but I still only get about 13mpg.
Now I know that the cam and heads are not helping the millage thing but for now untill I can get the room to put in the "magnum" based engine I want its what I have to work with.
I was thinking that a edelbrock "AVS" or "AFB" carb would be better for millage but not sure if it would make a lot of diffrence. Has anyone had experiance with just changing from a Holley to a diffrent carb and the effect it had on millage? Which one would be better for millage and yet be tunable for the amature like me? I can tune a holley for performance but never worried
about millage befor now. any help would be welcomed

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Author: admin