Either will work. Both will reduce the voltage down to approximately 9 volts so there is no difference there. I bought the second one you linked to, but from Classic parts for my ‘59 235.

Since you are installing a ballast resister, look for a coil that requires an external resister such as this one.

Phil
Moderator, The Engine Shop, Interiors and Project Journals

1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube
Updated to: ‘59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes
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