Poor spark off coil

72 RR, newly rebuilt 440 engine, I cannot get a good strong consistent spark off the coil wire. I get an intermittent spark.
I got no spark from the plug wire when coil wire is plugged into the distributor.
Any ideas?

new Orange 4 pin ECU,
new 5 pin ecu engine wiring harness, green wire with red tracer has no ECU pin
new CraneCam Fireball PS50 coil
new CraneCam Firewire plug wires
new 4 plug ballast resistor

intermittent spark from coil wire to ground & no spark to any of the plugs? Correct? start by checking the reluctor gap (want .008" at rest). Confirm that it is wired correct & the coil is being fed thru the ~.5 ohm half of the 4 terminal ballast & as you noted the other half to the red/green ECU terminal ain't used in a 4 pin ECU app. that'll get us started

Update, I got a better ground for the ECU box. Now I have great spark from the coil wire out. When I hook the coil wire to the distributor, I get no spark at any of the plugs. I put in a new pickup into the distributor. Rechecked airgap at .008, new rotor, new cap. Still no spark. Took cap off, rotor spins fine. The distributor was an off brand electronic unit bought off ebay. It must be a bad/wrong distributor? I ordered a Summit Racing Electronic Mopar Distributor SUM-850005. I don't know what direction to go if I still don't get spark at the plug wires.

You'll get a spark, no worries. Give me a call if you like. We can go through some "checks"

if the coil is putting out/delievering sparks to the coil wire plugged into the center cap terminal as the dist rotor/shaft turns then all that is left in the secondary current path from the center cap post to the plugs is the cap (replaced) rotor (replaced) & some if not all of the plug wires at least have continuity & these tend to be trouble free items, cap/rotor expecially & secondary voltage is intense & it takes alot to side track it (we're missing sumpin easy but I ain't seeing what it is)