No you dont have to take the fan off. once you get it off the pullies your can work it off around the fan. it might help to take lose the fan guard. I cant quite remember how the tensioner works but maybe there is a bolt on the front and you just move the pully so it losens. hopefully someone else will chime in on that.
When i had to do mine i cut it to get it off and then had to fiure out how to put it on with out ever taking it off. mistake on my part.
1998 Ranger XLT 4x4 Off Road
3.0L 5-speed 33's on 15x8 wheels
4.88 gears, expo L/S 8.8, locker in the front
T-bar crank, chevy drop shackles, and 3" BL
Lots of custom dents and scratches