For the third brake light/cargo light, I threw in LEDs I ordered from car lights and had no issues. Putting load resistors at each corner negates the biggest advantage of LED turns: the load reduction on your electrical system. Therefore, there is a better way to stop the hyper-flashing. You should be able to easily find replacements that account for the lower load of LEDs, or you can modify the one you already have by replacing the shunt resistor with a 0.1 Ohm resistor. It worked in my case, at least.