0.02 is his 2 cents.
Vacuum is measured at idle, since your is 2400 rpm's we'll ignore the vacuum until idle is under control. You likely have a vacuum leak, did you plug off or plug into all the ports on the carb? There should be 3, 2 small ones on the front and a large one typically in the rear. The large one goes to your PCV valve. Of the two small ones in the front of the carb, one is full vacuum the other timed. If you have a vacuum advance distributor, run your hose to the times one, but since your idle is high, plug them both. If you don't have plugs, you can buy them at the auto parts store, just ask for vacuum cap plugs. If the idle is still high, check your throttle linkage, this can sometimes hold the throttle open. If electric choke hook it up to power. If manual wire it open. When you rebuilt the carb, did you set the transition slot and are the secondary blades shut?