Figure about $240(Black Magic) for an electric fan that has a built in thermostat, you can do it cheaper buy getting a e-fan from a wrecking yard and wiring in your own thernostat, yet I have seen more problems with them than with teh Black Magic fans. You can also rebuild the fan clutch, by pullling it apart and regreasing it using the goo from the Toyota parts counter. I can't recall its actual name, but the parts counter at the dealership should be able to figure out what you need.

More than tread lightly. Leave it like you were never there, nor anyone else.
'90 X-cab 4.88's 33 BFG AT's, rr ARB, Headers, Ignition upgrade, cold air induction.
'91 X-cab 5.29's 315's BFG MT's, rr ARB, custom bumper and flatbed