I don't think that has anything to do with it, for three reasons; 1) you say that you have a hot coil spark, and 2) you have plenty of redundant grounds, and 3) the distributor does not need to be grounded, only the ECU needs to be grounded, and of course the spatkplugs,lol. If she cranks, then the plugs will have adequate ground.
As to the strength of the distributor driveshaft,at the reluctor end, it is stronger than the cap or rotor, so the little knock you spoke of should be a non-issue as well.
Wataminute! How are you testing for spark at the plug wire ends, versus at the coilwire?
