update: I did the install. There is no need for regulators, and I used a 25W 6Ohm resistors because 25W is closer to the native light bulb's 21W cold consumption. Everything else is the same as diagrammed by PatMatt.
While testing for a few minutes with turn signal on the resistor heated up to 160C (320F), that's way hotter than I expected and I haven't tested this for 30 min pressing on brake. I wonder if these resistors burn out at some point.
Not sure why the resistors were suggested to begin with, but I am thinking of replacing resistors with p21/5W (native to tail light) light bulb. I doubt that the light bulb will heat up to more than 100C.
Updates to come...
While testing for a few minutes with turn signal on the resistor heated up to 160C (320F), that's way hotter than I expected and I haven't tested this for 30 min pressing on brake. I wonder if these resistors burn out at some point.
Not sure why the resistors were suggested to begin with, but I am thinking of replacing resistors with p21/5W (native to tail light) light bulb. I doubt that the light bulb will heat up to more than 100C.
Updates to come...