The stock viscous coupled fan is the best and easiest, really......
Most people going electric hit the junkyard and get the "Taurus" fans. They are large two speed fan fitted to Taurus' and such with 3.8 l V6 engines. Lots of people running them on high horspower apps.
Lots of tech over at Pirate. Here are couple.
http://www.pirate4x4.com/forum/showthread.php?t=120931
http://www.pirate4x4.com/forum/showthread.php?t=293231
This is one I picked up for $16 at Pick n' Pull. I might install one of these days... They are a perfect height for the Rover rad and a little narrower.
http://i2.photobucket.com/albums/y45/Re ... rusfan.jpg
The Princess Auto (at least in Calgary) sells the motors for them new for $20 as well.
