Here's a shot in the dark:
When we first started up our freshly rebuilt 216, we couldn't figure out why we got no spark to the plugs, but had spark at the distributor.
Turns out the original distributors were NOT grounded, because for a few years there was a "polarity-reversing switch" on the starter that took the ground.
Any-who, when we figured it out, we grounded the distributor body (ran a wire from it to a screw on the engine), and we then magically had spark at the plugs!
Just-in-case you might have the same problem . . .
-Michael
