i have a 3:23 sure grip chunk in my duster that is not spinning both tires. it is doing a one wheel wonder. i am looking for someone that knows how to rebuild it for me. i will pay a fair price, and would like to find someone in the va, nc area so to avoid the shipping. any help would be appreciated. oh, btw, it is not making any noises or anything, but just is not locking both tires. any clue what a rebuild costs these day just for the labor?