I got those washer LEDs (I know, flame me all you want) and am jogging my memory trying to remember how to set this up: I want to wire it so that they work with the blinker, but have a switch inbetween so I have the option to keep them on all the time, or just off all the time and then active when the blinkers are on.

Where do I put the switch in parallel? Between the LED and power source or around the LED, I can't remember.

 

ground each LED light anywhere on chassis ground (the blinker ground works fine too if it's more convenient)
run a wire from the blinker + wire in the bumper (the pink one) and cut that new wire, put the switch in series with each end of the wire and repeat on the other side and you're set

there's lots of other ways to wire it up too, you could have it blink alternately
you could have it come on solid at night when you turn on your blinker (like our bright cornering lights)
you could have it on solid at night and still blink when you turn on the signal (either in unison or alternating)
look at my website in the corner rewire section for how to do some of these things

good luck rice boy j/k