Even 5-lug Thunderbird/Cougar rims will fit Taurus/Sable. I've been seing around town a 1998 LX with 1994-era Thunderbird LX wheels.
I put 1999 SE (5-spoke, polished aluminum 15") wheels on my 1993 Taurus GL and I love them. I scanned the pics today at my brothers house but he had to leave for work early (so did I, thats where I'm at now) so I didnt have a chance to post them. Sometime this week I'll get to it. I wanted 2000+ 16" alloys but $100 for a set of these was too damn good of a deal and therefor I was able to afford tires right away and get them on the car in a matter of days. I probably still wouldnt have been able to save up enough money to buy both the 16" wheels and tires on my measly sallary, lol.
Later, I plan to put these wheels on my 1988 Taurus L and then upgrade to 16" new style wheels with new GoodYear Assurance tires.