Plug is not oil fouled.....

Good suggestions, however, before I pulled the rocker covers etc. I'd pull all of the spark plugs and check them . . . while replacing them. they're due anyways at 100,000 miles. If you find one more fouled than the others then you have a better idea where to look. if you have to go further. Worst case you get all of them replaced and find nothing and have one more maintenance task complete.

Oh, and use a Sharpie to mark each one for which cylinder each comes out of. Post a pic of them here if you want, too.

Is the underside of the car oily? . . . especially right behind the engine?

OP, you might try replacing the PCV (inexpensive, and Google is your friend) to see if that helps with the oil consumption issue before delving into more time consuming and expensive repairs.

And also make sure that if there should be any O-rings, they are properly installed and in operable condition.

To answer questions: The underside is pretty clean for a car with 100K. No obvious leak paths. I've pulled the PCV and it is an ACDelco piece with an o-ring and it looked clean as well. I need to pull the valve covers and the plugs like was mentioned. Unfortunately its my wifes daily driver so it doesn't get much downtime (and she hates driving my truck so swapping isn't an option). I hope to make some progress on it in the next 2 weeks. Thanks for all the suggestions. This board is much more active than another I've posted to and I appreciate it.

Definitely understand that. At least you can keep tabs on it so it doesn't run out.