I'm curious about using a headlight switch for this? Might be a bit wierd at first... Pull switch one notch out for slow, full out for high then adjust the speed with the rheostat. Most of GM's intermittant wipers used variable resistance for the adjustable speed. Ford uses frequency. So as long as the rheostat would handle the low voltage/low current draw I dont see why this couldnt be adapted over.
Basicly if this idea worked out, you would go buy a new headlight switch W/harness (availible at aftermarket auto parts) and with a simple schematic, wire in the switch in place of your old wiper switch.
Whatcha guys think? If feed back is good I'll get to work on this asap
