Here's a pic of the single wire N/S switches. The one on the right was used on all pushbutton transmissions from '55-'64 and has an all metal contact button.
The one on the left was used on the '64 console shift and all '65-'68. The metal contact is surrounded by plastic.
The four switches used in the TF. The two at right are interchangeable if the proper wire connector is used.
Here are the internal levers used with the various switches.
The 3 pin switches are for the later model (68 and later) cars and trucks.
The 2 outter pins are for the back up lights and the center pin is for the safety switch.
There is a cupped rubber covered metal gasket that seals the switch, no O ring. The P/N is 2408123.