restoring bucket seat sliders

I'll get some pics posted today. The ones that came off the car that I am trying to restore for reuse are either like the ones on the left or the center (I'll compare when I get out to the shop this evening. Do you know what years the ones on the right are for? I ended up with a complete set of those in a parts swap and they seem to interchange with the ones I'm working on (same size and bolt spacing top and bottom) but the tracks don't have a feature to lock on the inside track, just the outside track where the knob is. Do you know what year they are for?
The one on the right is 67 bench seat. The other pair are later model bench seat but like I said, dont know what year they changed. The very latest tracks had white plastic/nylon roller cages.
I dont recall seeing any that didn't have a wire tying 2 latches/releases together. Seems to me only 1 would allow the seat to turn sideways in a serious collision.