Pinging on acceleration.

Car idles fine and cruises fine, but pings when accelerating. I suspect timing. It's a 1973 225ci Slant 6 with a Carter BBD 2 barrel carb in a 1964 Barracuda. It has an electronic ignition installed, not sure if that makes any difference. I'm not trusting my timing light. It's one of those electronic ones that has a bunch of stuff built in. The light is rolling the timing marks and says it's idling at 800 RPM where I can connect a tach to the coil directly and says it's running 600 RPM.

So, I'm going to hit up my dad and use his old school light tomorrow. From what I can tell it's supposed to be 0 degrees TDC at 750 RPM for this year engine?