Pinion angle and drivetrain vibration

Thank you all for your replies.

The Tremec app sounds good if you have access to the bell housing. My engine and transmission are obviously installed and I'm not looking to pull either, so I'm not sure how'd I'd get in there to measure.

I picked "level" as a datum, so those angles are all +/- degrees from dead level. Not sure if that helps my explanation.

To answer one question, yes, the transmission is pointing "up" (front to back) and the pinion is also pointing "up" (back to front).

The vibration occurs under acceleration and deceleration, or even keeping the same speed. It may be a little worse under deceleration, but I can't quite tell.

I'm going to order the Mopar 1*, 2*, and 3* shim kit. It sounds like I need to point the pinion "down" towards the front of the car by 2-3 degrees to match the engine/transmission angle.

Hope to report back with positive results.
Thanks again, and feel free to comment with any additional thoughts.