Slant Six has No power. will not accelerate

Was there any air flow when you sucked on the vacuum advance line? If so, you have a vacuum leak in the advance dashpot.

Have you checked all of the vacuum lines around the engine for leaks? The shaking idle is a clue that it could be such a leak. Also, you could have an intake system leak. Once you get through everything else, and when the eninge is cool and before the exhaust manifolds get hot, you can CAREFULLY try spritzing the intake manifold flanges and carb base gasket with tiny bit if gasoline; if the idle increases and smooths for a moment, you have found a vacuum leak.