3 ohm vs 1.5 ohm ignition coil

I spoke with Pertronix, they indeed recommend a 1.5 ohm coil for V8 applications...though I could not get them to opine specifically on the mopar orange box in that regard. I do recall someone on the slant six boards telling me years ago that if I'm removing my ballast resistor (which I did) then I should go with the 3 ohm coil if I'm using the orange box, but that advice may have been specific to the slant six, not sure.