Miles Per Gallon versus Set-up

[ubtripn]

I want to start by saying that I know there are those who say, "It's not about the mileage or if you have to ask" that type of thing and I respect that. I am asking the following question because MPG is a factor - for me. I use my truck as a daily driver around town. I am about to purchase a Crate Engine and my goal is to set up a naturally aspirated 350 to get the best MPG I can get. I realize that it won't be high but I want to see how high I can get it. Power is not a concern because even the least tricked out 350 will have enough power to do what I need. Not having a truck payment already helps off-set the cost of fuel but I would still like to know how others are fairing so:

1. What are you currently getting with your 350, your carburetor, your transmission and your rear-end combination?

2. What do you think the optimal set up would be to maximize mileage for a daily driver without using fuel injection?

This is for a 2 wheel drive. I currently have a 350 with an Edlebrock 650 and a 700R4, rearend is still not identified. I am getting around 12-13 now. (I think it used to be better.) I keep the oil and filters fresh along with the plugs.

Thanks for any information you can provide.