I installed an electric cooling fan on My S-10 in February or so this year. [...]
I wish someone made an electric clutch, like an A/C compressor clutch, that drives a water-pump mounted fan. Then you could install a massively agressive pitch fan with enough reliable HP to turn it -- but only when you needed it, with a thermostat.
I always thought that on the later AMCs with TF autos, the TCS (transmission controlled spark) swtich would be perfect for disabling an electric fan. The switch closes (or opens, I forget) at 35 MPH, pretty much when you're getting a radiator full of air from forward motion alone.