After digging around for a while, I was able to pull a great break down from the
"Engine builder's handbook", It states....
"Once the clutch is off you'll have a clear view of the flywheel. If an automatic transmission was used, a flexplate will be in place of the flywheel.
There's now much difference between removing the two except for the additional weight of the flywheel."
Flywheel is usually either cast or billet, noticeably thicker and heavier, and will have a large smooth surface for the friction disc of the clutch to make contact with. A flexplate is usually just stamped steel with the starter gear welded to it, as was said, the flexplate is used in automatic cars and is basically just a way to connect the torque converter to the crankshaft.
And right here as part of my thread from "CherokeeForum.com"
An automatic will have a "flexplate" - the torque converter makes up the flyweight rotational/inertial mass (in manuals, it's provided by the flywheel and clutch cover.)
Pioneer/Barnes should make one - I've bought a few for RENIX from them, and RENIX is less common. I don't see why your local can't come up with a part number for you - but you might want to find a new local (AA and AZ aren't exactly my idea of a "good local" anyhow. Most chain 'countermen' have delusions of adequacy. Try a NAPA or a Carquest instead - they're somewhat better.)
The only place I was ABLE to find a reasonable replacement of the part is from this site www.partstrain.com
They have live support chat in the event you have a question or difficulty in finding a very specific part.
I hope this helps with any future questions about the two - Enjoy