RPM Drop From Nuetral to Gear

Having the reluctor "off" is not a good thing, Google "rotor phasing"

All Mopars change either points gap (dwell) or reluctor gap with vacuum. That much, however is a "big" change. Make darn sure the thing reluctor does not strike the pickup.

Frankly, when I have issues "that could be" ignition related, I immediately pull the vacuum line AND LEAVE IT OFF until you get things sorted out, and of course if the symptoms change dramatically, you also know you are "in the area" of the problem.