I remember seeing an aftermarket generic kit for this for around $90 that you patched into the existing wiring.
I have it on my Explorer and its not worth much more than $90 to turn the lights on about 2 minutes before I would have done it myself.
I also remember reading a number of members had problems with the OEM system (Surprise, surprise!) blinking on and off and needing a reprogram or the like.
Mk1 switch on the left work fine for me.