Any luck on the wiring harness? I'm still in the pre-ordering phase and would love to get the towing package on a 2500 SV, V6 but according to dealer, can't get it from factory. I want the v6 for better mpgs and in driving it versus the v8, the v6 had good power and acceleration. I would be towing a small rv occasionally which weighs less than 3000 pounds. I will need a 7 wire plug and brake controller also. It appears that etrailer has a hitch receiver for $150 that is designed for the NV. Jay