In general, the LED bulbs which replace common filament bulbs, give approx
twice the light, run cooler, and are supposed to last 10 times longer than
their filament counterpart.

My impression is that the resistor is in series, so that would probably
serve to limit or reduce current draw.

I finally got my answer, though. Found some on Ebay and they say they're
direct plugin. So, if any resistor or whatever is required, it's internal
to these 1156 replacements: 280074315883