I registered when Flex 1st posted a link to receive a kit if your radio was in the update. I didn't contact Flex again and today a package came in the US mail. It was my kit, I installed per directions and everything went well. From a 1-10 in difficulty it was around a 5. BTW my heat sink in my 6400M was ready to fall off it was tilted to one side and very easily to remove. The biggest point of difficulty too me was getting the board plugged back into the motherboard and getting the screw back into the stand off. Plenty of light shinning into the radio for these old eyes was needed.