Hei conversion troubleshooting

Ok, this is getting insane.

Put a brand new module, brand new coil and hung all the HEI stuff back on the car.

Engine will rev ok in park, as soon as you get any load on it, starts backfiring and hesitates bad.

Disconnected field wire, no difference. Changed timing from 15 to probably about 20 btdc, no difference.

Checked coil positive terminal and ignition control module B terminal, both getting full 13-14v when poor running condition is happening.

Put my see-through rotor cap on. With no advance in, rotor fires on leading edge. With vac advance in, trailing edge. Stays pretty close to centered on contact the whole time. And when shining the timing light to see the rotor passing the contact, it only occasionally lights up as it is passing, usually i can only see the spark arcing from rotor tip to contact.

The spark, however is weak and orange. It is super intermittent. Gets brighter and fainter as engine stumbles and runs poorly.

I don't know what else to try at this point. I guess moving the module off the distributor so It can't ground to the engine block is the last thing I have not tried. After that, i guess its back to points.