For refrence (in case the kid at the autoparts store can't figure out what kind of switch you need) Freightliner uses this same type of switch for their power windows in many of the older (FLD120) and proabably new trucks too. The switch is made by Cole-Hersee and it'll have six terminals: two in the center are power supply and the two on each opposing end are power out.
Don't forget to protect the system with a breaker or fuse. :shock: