Bob, Wrenchbender is right the gasket between the manifolds is for heat to the intake it will not be a source for a vacum leak.
What I was refering to, is that if the manifolds were seperated and put back together tightly, before being mounted to the head, the mounting surfaces may not be flat and there could be a vacum leak. Bolt the manifolds together loosely, then bolt them to the engine and torque in place then tighten the four bolts.
Change the points and condeser they aren't expensive, is your coil wired correctly,It will be something simple.
