Does a 2004 Lincoln Town Car have a cable attached to the transmission which controls the gears? That’s what mechanic said…costs to replace because transmission must be removed.
I think it does have a cable that actuates the transmission, the best I can find. But, that said… If you doubt what your mechanic is telling you, maybe you should take it to another mechanic.
In addition to what @Mustangman said, let me add that if you’re looking at an expensive repair, it’s not a bad idea to let another mechanic diagnose the problem to see if they come up with the same problem and see how much they want for it too