Unless the LEDs have resistors already built in, you're not going to be able to fix the fast blinking without cutting wires. You can get loaded LEDs, but you'd have to look for those specifically. Load resistors aren't a big deal to install, but you also have to keep in mind that they get as hot as a regular bulb because they're taking in that additional current to slow down the blink rate. It's not a big deal to splice something in, or you could find a plug sometimes even at Autozone that would allow you to plug and play the resistors into the line without cutting the factory wires. I haven't looked for those harnesses, specifically, but I know it wouldn't be too much of a headache. PM me if you go that route and have any questions. I had to install the load resistors in my motorcycle kit when I integrated the blinkers into the taillight. Good luck!