Originally Posted by Mxfrank

Take two wires, attach them to the poles of the new sensor with a couple of crimp terminals. Run them over to the drier, and attach them to the two poles of the pressure switch with piggyback connectors and crimps. You can bundle them in electrical tape for a neater look. Done.

If you want to use an original style, single terminal switch, be aware that the case is the second "contact", since it's grounded to the block. You would have to figure out which of the two leads on the pressure switch is ground, and which is "hot". Then you would run a single wire between the terminal on the new switch and the hot side of the pressure switch.

If you have an old part, you're going to have to figure out exactly what it is, because they aren't all the same. It could be a sensor, which drives a gauge, and would be useless for this application. Or it could be a thermoswitch. If it's a thermoswitch, the temperature set point is important. It may be an 85C switch for the fan, or it could be a cooler switch for the glow plug system. Just because something looks like a fan switch, doesn't mean it will work for your application.

Can't help with the fan.