Axle Hop continued...
Well I checked under the car- No orange spacers up front and I don't see any evidence of the differential or driveshaft making contact on the floor pan anywhere.
The noise I am hearing isn't so much a 'Thunk in the Trunk' as the TSB may be addressing, but more of an actual hopping of the axle(s) upon acceleration. Nothing is hitting the bottom of the car, it's the tires bouncing on the pavement.
In the old days, we'd slap some traction bars on the beast, but with the IRS, what are my options?