Check into using one of the Zenith 2-barrels for truck engines from the mid-1940's on up to mid-1950's. They can be adapted to different CID's by changing venturis, etc. There are usually a bunch of them on Ebay at pretty reasonable prices. You'll need a 4-gas exhaust analyzer to set one up properly, and it would be great if you can rig it to be mobile so you can check the mixture under load on a road test. I've logged hundreds of miles that way while tinkering with main jets, metering rods, ignition timing advance curves, etc.
Jerry