Performance mixed with fuel economy!?

Thanks for the input.
A gen 3 hemi would be very cool, but no power steering, (call me a sissy).
Trying to stay with the LA engine to keep the 340 hope alive.
Forgot to mention that I was planning on swapping to a 4 speed also; then I could use the much maligned OD manual. Upper teens for mileage is tolerable, I want to drive the wheels off it in retirement (12 months left of 12 hour rotating shifts!).