Correct Ballast resistor

Rainy Day Auto said

There are different resistors in each kit ???

For Mopar... Small Block 273 318 340 360 Electronic Ignition Distributor Kit | eBay

MOPAR 318 340 360 HiRev Electronic Ignition Kit Resto OEM Plymouth Dodge Chrys | eBay

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Looks that way. They might both have the same resistance reading.
Visually the distributors look the same but have different ECUs.
For a 340, I'd say the odds are better that Rick's is going to be a better match. Internally, the curve in his distributor has been set up like the old MP or 440 HiPo.
Getting the right timing curve is more important than any other characteristic. Properly curved dual point will beat an improperly curved anything else. No amount of spark energy is going to change that. A lot of sharp racers found that out in the 70s.

edit: added link to 440 timing curve