Nathan: please... I have owned many of these V12 cars and have some experience with this issue: replace the fan and the viscous unit and you will not need to worry any further (assuming the rest of the cooling system is in proper condition). The new black fans are much better than the original white ones, and they do not crack (made of different material). The part number for the new black fan is EBC 4553. The viscous unit is EAC 4751. The fan relay (crucial) is the red cylindrical relay and it is DAC 1028.

 

That's what I plan to do, I'm sticking to original, no electric conversions.