I recall coming home from college on the weekend to blast out a valve job on a 350 Nova. Brought an EE home with me to check it all out. Well we did the damn valve job ( mostly just lapping frankly, they werent bad) - finished bolting it all on at dusk and fired the mill up in the dark.
Had a sparkshow going on. A valve job was done to fix a bad $10 set of wires. Oh well! Me and the EE learned about proper diagnostic procedures. Should have done a compression or leak down. But I wanted to show my frat buddy the shop I worked in , and a little engine machining lesson. The poli sci major teaching the engineer. Fool ! But I taught him well!
I always test wires with a VOM now. New or not, ALWAYS. In fact one of "tune up " procedures now. I test the wires when I RnR the plugs. I had another incident with a new set of wires on a daily. Bought from "Natiopnal Auto" to date that incident. Found a bad one with my multitester ( as made or I horsed on it and broke it upon install).
CHeck the resistance in the wires. Performance spiral cores should be from 800- 2000 ohms depending on length. ( although I have checked some NGK's that register near 10K ohms). Eliminate them as an issue. I'd then pop the cap and inspect the rotor carefully. PS, if you decide to pull the plugs again, certainly check the valve lash.
That would be my step 3 - wires - rotor- lash. ( you could also do a compression test afterwards to eliminate sealing as an issue)
If its a mid throttle miss, than its very likely the carb. Airbleeds specifically. Step 4......
You'll find it! Process of elimination.....