led tailight bulbs

I've tried a 2-prong 'orange colored' LED flashing unit which did nothing at all. And also tried a 3-prong unit with 1 ground wire.
The moment I hooked up the ground wire the unit started clicking already. So I might have a current leak in the system. Didn't measure at the time.
Haven't tried reversing the polarity with the 3-prong unit yet.

Installing resistors again to make this stuff work is like going back to the dinosaur age.

Here are some posts I made on my website about trying out (China-bought) LED lights.
(Perhaps not quite informative at the moment, but when I get this figured out I'll post partnumbers and such)

1973 Dodge Dart – LED lighting

LED turnsignal lights
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