I purchased the FK-35 to control my Mark VIII fan. I think that our fans are the same... I am also in the process of gathering the stuff to do a 130A 3G swap. Since the stock alternators are pretty much maxed out from the factory, it's smarter to upgrage so you don't tax the charging system too much.
I just learned that summit sells a 4 guage wire kit for the 3G swap for less than $20.00 verses the kit that PA performance sells for around $50.00.