Three on the tree rebuild kit???

I just picked up a 70 dart four door. Factory 318 and three on the tree. The shifter is a bit sticky and it appears that the bushings on the selector are worn. With someone in the car operating the shifter, I can see the selectors binding up with eachother when you go to put it in first gear. I've never never had one of these apart so I'm not sure exactly what's all in there. Does anyone offer a "rebuild" kit for these? Any help is appreciated.