I've been thinking of doing this for a while but wasn't too game as the only thing I could find was the Samba thread on adding a micro switch. The 74 washer uses a similar system in the wiper stalk but space is really tight and mounting a micro switch is not possible. I ended up just removing the switch and fashioning a bracket to mount the micro switch, the trick was to pull the end knob off the micro switch which revealed a hollow tube which I shortened slightly for extra clearance space. I then found a old fashioned nail that was in similar diameter to the plastic shaft on the old actuator and cut it down to size to fit in between the stalk and micro switch. I then soldered the whole thing, added some electrical tape around the end of the micro switch to avoid any short circuits from the assembly body and then ran some wires and to where the other micro switch under the dash was and bypassed that (I already had an electric pump washer bottle), so now I can activate the washer by pulling up on the wiper stalk!