I bit the bullet last week and had a local mechanic who is normally very good replace the alternator. I drove it for the first time yesterday and felt a very noticeable vibration at idle and low speeds.
I looked at the replacement alternator and it doesn't have the long nose as the original had which I assume was the clutch assembly. Is there a failsafe way to tell what was put in so that if I go back to him, I have some facts I can give him?

 

You can remove the fan belt and this way you can verify the vibration is gone.

 

Was the part from the aftermarket?

 

Yes which I'm guessing is where the problem is. After I posted, I did some poking around on the internet and came up with this. There's probably some self interest but it still makes sense.
http://www.decouplerpulley.com/basics.cfm

 

Has anyone else purchased a alternator with out the "long nose" as described by mfahey.

Did the alternator aftermath work with some longevity and without effects on other pulley devices on the car?

Mfhaey please keep us aware of the progress

 

I try to buy mopar, when they have the part still available.

 

yep. some aftermarket parts are just a nightmare.