Never have seen a stock Delco dual point but Harmon Collins and Mallory both made a conversion plates in the 50's to use dual points, the ones I have all use an exterior condensor. I believe Hudson made a dual point at the factory.
'45 Ford PU 66 Valiant wagon, leaning tower of power. 79 Chevy C10 w/250 02 PT Cruiser Convertable