Do you have a manual tranny or automatic?
In my auto, there is a small access panel under the car that you can remove to look at the "flex plate" - which is the ATX version of the flywheel. I have a section of my flex plate on my Mercury that was all ground up, the dealer I bought the car from sent me a new plate, starter, and I did the work myself. WHAT A PAIN! Never again will I do that!
To check the teeth on the starter, you'll have to remove it. Not a simple job on an automatic equipped V-6 car.