So I did a 5.3/4l60e swap in my 71 c10 and I cant get in to shift into 3rd or overdrive. So far i only have L1 L2 and reverse, with the 20 pin connector pulled from the trans it does go into 3rd.

Here's a list of whats been done to it so far.

.Borg warner clutches/seals
.Borg warner forward and reverse sprag
.Molded piston kit
.Beast sun shell
.Transgo shift kit
.Internal wiring harness
.All new solenoids and sensors

My first thought was the input sprag was backwards,so i pulled the transmission out to check and it does lock in the counterclockwise direction.

Any help is greatly appreciated.