If you can find a spare intake manifold, I'd suggest adapting a Holley #7448 350 CFM 2-barrel to the engine. Just using an adapter plate probably won't help, because you need to open up the throttle base area for more airflow. We use the same carb on the 350 V-8 race engines, and make over 300 HP at 6,200 RPM. The 292 engine should wind up to 5,000 RPM or more on this carb easily, and you can gear the rig accordingly. Also, the Holley is VERY adjustable in the main jet and power valve department. I keep at least 6 sizes of jets and 4 different power valves in the race tool box all the time, to compensate for temperature, atmospheric pressure, and humidity changes on race day. JEGS sells those carburetors for about $250.00, brand new.
Jerry