An out of phase dizzy will usually cause the spark to jump to wrong cylinder, either side of correct one, so it will normally pop and bang like mad from either induction area or exhaust.
With the rotor arm aligned to one of the plug lead posts on the distributor cap, when the white wire is grounded, the spark should pass from coil to cap to rotor arm to plug post to plug lead to plug gap.
Tim has tried this test and it only gets from coil to distributor cap no further which points to a cap/rotor arm problem to me, or the lead from cap to plug.
As JacMac suggests, connecting an inductive pickup timing light and cranking would prove that the ECU is firing the MSD, even if not in time and also that the ECU is being triggered.