http://www.discountedwheelwarehouse.com/Mercury___Vehicle_Bolt_Pattern_Reference.cfm
View the link below.
Five. in a pentagon shape.
Same year Mystique and Contour
Unfortunately the lug pattern is different, the wheels will not interchange. You can use Thunderbird or Cougar wheels.
What is the lug pattern for a 2000 BMW 323i?
Yes
I'm assuming it is the same as the ( 1996 ) model year of Mercury Cougar : ( there are 5 lug nuts for each wheel / total of 20 )
5x120
5x135
5x100
5x5.5
Bolt pattern is 5x108