That's an interesting idea, but I doubt it's going to help you find the problem if you haven't already.
For instance: Say you do as you are suggesting and the vacuum leak involves the manifold gasket but is located UNDER the manifold. If you pressurize the intake, the air is going to bleed into the crank case and could end up burping through your pan gasket, or some other strange place, which wont help you locate the source of the leak.
Since you're already considering the trouble of removing the carb and other connections, why not remove the intake manifold as well, and replace the gaskets using a good gasket sealer and RTV sealant instead of the cork end gaskets. This way, you'll know it's not in the intake and can focus on external connections. It will also give you an opportunity to inspect the back side of the intake for cracks, which could also be the cause of a vacuum leak.
Good luck!