Yes, you're just missing the choke. Otherwise your AVS looks to be in excellent original condition. They are very easy carbs to clean and rebuild. Straight forward design, gas doesn't leak out of them, and they make good power. Set them up as designed by the factory, and resist the urge to loosen the secondary air valve (what looks like a choke plate over the secondaries). All you'll get is a bog. The brass floats shouldn't ever give you trouble with soaking up gas. Make sure the choke pull-off holds vacuum. Ensure the rods and pistons move freely. The rods are delicate, so insert them AFTER the carb top has been installed.
When you clean out the various air bleeds and jets in the primary venturi clusters, just use solvent and compressed air. And they can only go in one way - look for a little notch on the underside mating surface.
The AVS (air valve secondary) is a more advanced design, an improvement on the AFB (aluminum four barrel). The primary side is similar to the AFB, but the secondary side is the precursor to the Quadrajet and Thermoquad designs. The primary jets and rods of the AVS are unique to it, and don't interchange with the AFB (unless you ALSO replace the dimpled step-up piston cover plate with the flat one from the AFB). The secondary jets however, are the same design.
