727 no 3rd wont shift

installed a suposedly built 727 in my 74 dart sport and it will go into drive no slipping start off in 1st gear. I can pretty much red line it and it wont shift into 2nd untill i manually do it (whitch is kinda fun) after im through 2nd i manully put it back in drive and it stays in second.

Ive read the forums and cant find this problem. Ive tried adjusting the kickdown rods but i realy dont know what im doing, nothing i do seams to have an effect or improve i slightly