This thing is driving me nuts. The trans is professionally rebuilt (‘76 Volare), originally a floor shifter and the shifting mechanisms are all new.
I put it in Park, shove the lever on the trans all the way back to Park position and tighten the linkage rod. Park works fine, move lever to Reverse - it’s still in Park. Move lever into Neutral and it goes into Reverse. You can the partially select Reverse and it stays in Reverse. Neutral is Drive, push it back a little over half way back, it’s finally in Neutral.