LS Swappers - need some ideas on a P035x coil circuit error

[Jackson's Dad 64 C10]

This post reminds me that I have never done a build thread in the 7 years we have been working on this turd! My son and I are finishing up a long term project 1964 C10 short bed, fleetside big back window truck. It came off the frame, No Limit suspension, air ride, lots of changes... We transplanted an LY6 6.0 out of a 2010 Silverado 2500. I've integrated the BCM (don't quite know if that is completely sorted yet), using an E38 ECM, factory harness reworked by me, 6L90E trans with the Lokar electronic sport shifter, and Dakota RTX instrumentation with the BIM.

First start up was Monday night, after chasing our tails trying to pressure lube the engine. FINALLY got oil to all 16 rockers. The truck started on the first try and idled pretty smoothly, but I'm getting P0351, P0352 and P0353 errors. The DTCs are Ignition Coil Primary/Secondary malfunction (for A, B and C - Cyls. 1,2,3). I'm stumped on diagnosing this one. I've followed most of the troubleshooting chart, minus checking the frequency of the ignition control circuit. I dove straight into switching coil packs around - no dice, and I've checked voltage on the circuit (battery voltage). I ohmed out the control wires from the ECM to the junction connector at the coil rail, and all the way to the individual coil pack connectors. The control wires were all .1-.3 ohms resistance. The common low reference wires were fine too. I'm starting to wonder if the plug wires aren't the issue. We used the same Scott plug wires we used on my son's Gen 3 swapped '91 Z28, so we know they work on the LS platform. Am I missing something obvious here, or am I getting down to a bad coil driver in the ECM? I'm mainly looking for a gut check on anything that I might have missed. Thanks in advance!

-Chris