[rsk289]

The wiper switch you show doesn't look like a PRS7 to me, but if it works who cares?
There were several variants of PRS7 switches, all with a pressed aluminium casing. The one for a Cobra wiper motor (DR3) needs to be the 6-wire, not the 5-wire. The switch will power the wiper motor in reverse to park the blades down below the screen - they do a fun little dance when you switch off. The switch is the same as that used in XK Jaguars amongst other cars.
Roger