Poor mans Hemi car. (M-body)

I can search various sources both dealers and otherwise.

Wasn't able to get the part number off of mine. I thought the tail light was just about ready to come out, but the bumper filler panel is still attached and I'm not laying on my back on a concrete patio with the temps in the teens and windchills in the single digits. All I can get is the engineering number and it's the same both sides. So, dla? Got the part #?