you have to take the radiator out. In park, the engine should be locked well enough to just unscrew the bolt with a little leverage from a breaker bar. To get the balancer off, you need a puller, and the puller will not fit on there with the radiator or fan on the car. You may want to replace the timing cover seal while you are at it - but it is not necissary. If you are concerned, this may be an easy time to check for TDC. My philospohy is if there is something easy to do/chage while it is apart, you may as well do it and do it right. I have been burned too many times from having to take things apart to chage something I was too cheap to change while I was in there the first time!
kevin