What rear gears for a 302 F150?

Small blocks are a somewhat new to me. Can anyone tell me what a good fuel economy rear gear would be in a 79 F150 that is getting a 302? The 400 is worn out and I'd like some better mpg's so I'm going with a smaller engine. It seems to me the stock 2.75 rear is way too high for a little 302 economy engine. I've got either a C4 or a C6 to go in. No AOD on hand. It's just gonna be a daily driver, not much hauling. Would I get better mileage out of staying with the 2.75 and dropping in a 351W?
Thanks for any input,
Tex

With the 302 a 3.55 gear would be good with a 30" tire.

The 351 might get better mileage..Especially with a 2.75 gear..I went from that exact setup getting 10mpg to swapping in a 429 thunderjet that got 12-14mpg and had 10 times the power...I would go with no less than a 3.00:1 gear with the 302..

Thanks for the info. What sounds ideal is if I could find an AOD to drop in with the 351W.

Tex

I had 3.07 gears in my '90 f-150 with the 5.8L, upgraded to 4.10's after lifting it and putting on 35" ers. but then again i have an e4od; in your case I would stick to something in the 3.23-3.55 range. especially since you are considering a non-od tranny.