What purpose does the interlock mechanism serve on a console-mounted horse shoe shifter model? My 69 came with the horse shoe shifter and cable linkage, but no connection to the interlock.

The mechanism locks the shifter when the key is in the "lock" position. It also activates the reverse lights, I believe. It's mainly a safety feature so you can't take the car out of park without the key.

I am missing the rod between the transmission shifter stud to the idler lever on the frame support. Will that item be available somewhere on the market?