As an old Hot Rodder I have built many engines for speed but have done a few for MPG...torque. A 40 Ford coupe with 289 .030 over, truck cam making max torque at 2200 rpm, an aluminum 4bbl intake made to accept an Autolite 2100 2bbl, electric fuel pump, flex fan, Mallory dual point, Accel coil, big wires (7mm?), balanced, dual glass-packs, stock heads polished, big car flywheel in front of a 303 three speed, 2.79 rear, 29.5" rear 70 series radials and skinny fronts plus it was low on a 3" dropped axle. About 250 HP and 24 MPG highway without overdrive. Your plans look like they will work great. Looking forward to the 3.0 build as mine needs work at 226K. Good luck.