I'm in the process of deciding on the carb set-up for my 302 that will go in my '52 Chevy 1-ton. I have the original manifold that fits the stock Holley AA-1 and a mil. manifold that has small 4-bolt pattern. I have split exhaust and eventually plan to run a Clark 280VO (0.8 OD) driving a 4.11/4.10 rear end. This mean I'll never be running the engine up higher than about 3600 rpm. The engine is stock except the cam is a Performance 254S grind from Delta Camshaft. I'm looking for reasonably good fuel efficiency without losing low-end torque and hauling capacity. The options I've been considering are:
1. Stock AA-1.
2. Dual AA-1s with one set up as a mechanical-progressive secondary.
3. Progressive two-barrel; Carter/Weber or Holley/Weber.
4. A small 4-barrel with smallish primaries and bigger secondaries.

I would appreciate comments on the pro's and con's these options as well as on vacuum vs mechanical-progressive secondaries. On-line guides seem to agree that vacuum secondaries are best for automatic transmissions, but that's not an issue here.

Thanks