Several weeks ago the 55 bird would not start.  No spark from the coil.  After a couple of day of poking around the distributor area, I had spark from the coil it started.  Again today.....no spark from the coil.   New coil installed, still no spark.  QUESTION....im assuming the ground for the distributor is the fact that the distributor is in the block and held with a clamp.  The battery positive is bolted to the block at the water pump.  Am I missing something regarding the grounding of the distributor?  I do have the coil positive post connected to the distributor and the coil negative goes to the "ignition" circuitry, since this a positive ground system.  This info. came from the CTCC and the ford electrical assembly manual.

Thanks, Charlie