Your response is not one that would garner much, if any, help on this forum. There are a few reasons for the responses you received:
(1) Most Contique owners have a single DIN opening. You didn't specify you had an older model with two.
(2) Most of the "regulars" on this board dislike Ford OEM stereo equipment to a great extent. In short, it's generally sub-par and can be replaced with much better equipment that will look factory if so desired. You could spend much less than what that ebay auction will end up as and get better equipment. You didn't specify you wanted a factory look either (which can still be had with aftermarket equipment).
(3) Most people have ditched their cassettes long ago. You didn't specify you wanted to be able to listen to cassettes.
All that being said, here's your answer:
They'll work but will probably require some rewiring. It depends on what harnesses are used in your car and whether or not you have the "premium stereo" option, which has an external amp behind the glovebox to deal with. You'll also have to deal with the Mach amp, which could be a PITA.
I just wanted to add that there are some aftermarket options that fit your needs and would cost about $350 with vastly improved sound quality.
The top one is a Kenwood cassette player that you could pick up for ~$150. The bottom one is a single CD player controlled by the receiver with a graphic EQ that costs around ~$175.
Blaupunkt also makes a 6-disk in-dash changer which can be controlled by one of their in-dash cassette players. It'll use the same setup as the Kenwood. It costs $250 plus a Blau cass HU ($150-ish). Here's a "little" pic of the changer. With the right Blau HU, it'll look very similar to stock equipment.
You can use a Sony single DIN CD player with any cassette player. It's got pre-amp outputs which would work with an aux input, and it's also got an FM modulator which would cover any HU w/o aux inputs.
Just trying to throw some options out there for ya.
