Auto Console Shifter: Five Positions?

I feel like an idiot for asking this, but my brain just cannot grasp this. I’m swapping from a column shifter to a console floor shifter, stock set up except the shifter which is a new PG Classics clone of the original Mopar shifters. The tranny is out of the car as I’m also swapping the torque converter and replacing a few seals. The shifter, which looks identical to every stock floor shifter I’ve seen, only has five positions to move through while the tranny feels as though it has six positions, which makes sense: Park, Reverse, Neutral, Drive, Second, First; so six positions makes sense. When I connect all of the shifter rods and shifter to the tranny it seems as though I’m only moving through five positions, which is what the shifter has. What am I missing? Can someone with more common sense explain this to me as I’m sure this is a simple answer. Thank you.