[mightymoose_22]

If the engine isn't running you will need a vacuum pump to test for leaks. Applying vacuum at the vacuum port on top of the manifold will let you test for leaks around the manifold. Basically, if pressure holds then you know there is no leak. If pressure doesn't build or slowly leaks then you will need to isolate each system to find out where the problem lies. If you do get the engine running, you could check for leaks with soapy water along the mating surface of the manifold. If the water finds a leak you should be able to hear the engine pick up or run smoother.

However, since the engine isn't running, let's put the vacuum problem aside for now (although that could have something to do with it having died in the first place).

Is your crank sensor plugged in?

I believe you said you have spark... how did you verify that?

It sounds silly, but are the plug wires in the correct order, and seated firmly on the plugs?

If you have the know-how... disconnect your ignition switch and attempt to start the car with jumpers rather than the key... perhaps the ignition switch is worn and not making good connections.

Just some thoughts... these engines are pretty straightforward. There are only so many things that can prevent it from starting.