Hi XXXXXXXXXXXX, my name is XXXX X and I can help you with this.
It sounds like your automatic seat motor is wearing out.
Because it is an automatic seat, it moves every time you get in or leave your vehicle, so it get a lot of use, so after 10 years the bearings may be wearing out.
Because a dealer shop makes its money from labor and parts sales, they will first listen to you, then they will test your seat then they will recommend a mechanic look at it then the mechanic will remove the seat, he can't make any labor money unless he does some labor, he'll remove your seat and bench test the motor to decide if it's the motor or the runner bearings that have gone bad, then the dealership will call you with their recommendation, and the mechanics, then with your seat out and the motor removed, you will be asked if you want them to fix it.
Sorry about all this, but this is a case of "been there, done that", more than once since my first New cars in '72'.
My problem with this is that the Dealer may be the best choice even though the cost will be quite high.
If you are a 'do it yourselfer' and don't mind used parts you can try that route if you can find a reasonably priced replacement seat base at a salvage yard. One that will bolt right up to your seat and has a good working motor and glide rail set up. Since most full sized Ford, Lincoln and Mercury cars use the same base parts, I don't thing there will be a problem finding on that will work for you.
I remember parking my T-Bird next a friends Continental. The only body differences were the opera window in his Linc, the grill in his Linc and the trunk lid on his Linc. These along with his interior appointments were the only difference. Our seat base and glides were the same too.
Since your discription says, "bad motor or seat glide" I am automatically assuming the worst here.
I hope this helps you decide what to do, I know I really hate to give over my ride to someone else if I can do the work, so I do hope you are interested in DIY because of the cost you will find at the dealers for, what is, after all a used car problem, not a new car problem requiring a, supposed, dealer professional with up to date knowledge.
After 10 years every mechanic who works on seat problems will know what to do for yours.
Sorry again GrandMaster7, but to me a dealership is a last resort or something I do only with warranty work because of their expense and their built in belief that they are right, which is not always the case.
I hope this helped you, and
Thanks for using Just Answer
John D
Retired General Mechanic
Over 20 years as a general mechanic. Last 10 years specializing in Ignition, Lock and Electrical