I used regular PS fluid (not ATF) in my 2002 Century.
If you look back at my older posts you'll see that I neglected to change my OE ATF until about 70K and my system was groaning and moaning. I did a few TB changes with regular Walmart PS fluid and it helped. When I added about an ounce and a half of Auto-RX it quieted right down. I ran it about 1000 miles with the A-RX in the system and did a couple of TB changes and my PS system never made another noise again.
PS: I still have those Century parts for sale that I mentioned in that thread a few weeks back (and some that I didn't mention). I live in Orange County so it wouldn't involve shipping.
Thanks for the info. As far as the parts go, all I need is wires and plugs, everything else is done. I have credit due from AAP and as soon as I get a chance I will go there and use it up. Thanks for the offer, and the help!