Radiator Fan Switch??

I have a 90 Transport 3.1 v6, need to know where the radiator fan switch and relay are located.

the relay is mounted in the relay center under the hood and should be the farthest one towardt eh drivers side. The switch is located near the t-stat housing on the drivers side of the eengine, and should have a round(as looked at from above, mushroom shaped from the side) plug with 1 terminal.