You can run out to the Pick and Pull and go under the dash of any of the late 60-70's Ford pickup and grab the switch - and the connector too. I picked up one of these on Sunday, but then pulled the brake plunger from the 65 sedan in Sequim later that day to use the later model switch that goes on the plunger shaft and pedal arm:

http://www.falconparts.com/ford-falc...CH-179p737.htm

So that's the direction I am going and I don't have need of the one I got from the Pick and Pull anymore - if you want it. The one I grabbed had the nuts on it, which you would need to adapt it to the 60-64 cars.

The 65 was the first year to eliminate the pressure switch - which was always scary.

There is nothing I can think of either as to how this switch (or multiple others of the same kind) could cause the pedal to go to the floor. Just doesn't work that way. It's a trap, not a by-pass device. You need to have a means for fluid to by-pass to have it act that way. The scary part with these was that when their seal failed, they were a by-pass device, but the evidence of it was no brakes, or a pretty bad leak coming out of the switch.

So, have you tried just to plug the port with an 1/8" pipe plug to see if that causes one thing or the other?