Barracuda No-Start

Hello Folks! I got a baffling ignition electrical issue! I have a 1968 Barracuda that I had to pull the motor to replace the freeze plugs between the engine and transmission. I did some cleaning and painting before I put everything back together. I went to fire it up when I was done, I got no start! I converted it to electronic ignition many years ago. I tested power to all the components, 12+volts to everything, I tested individually the ballast resister, coil, ECU, distributer pick-up. All check out good! I tried replacing all of the components individually including the cap and rotor. Still no-start! I removed the distributer with everything still wired and cap and rotor installed. With the ignition on, I spun the distributer shaft and got spark! I re-installed the distributer and get no spark now! What do the experts here think I got going on?

Thanks in advance!