Filler panel

I purchased an aftermarket front filler panel for my 1989 Caprice 9C1 and noticed two tabs beneath it (one on each end below the headlight area), and assumed they were designed to clip onto the top edge of the bumper. The cracked-to-pieces original panel did not have these.

I had my body shop paint and install the piece, but was very disappointed to find they had installed it without removing the bumper, therefore leaving the tabs above it and creating ugly gaps on either side. The shop claimed it was impossible to get the tabs under the bumper, but I don't believe that. I would assume that it can be properly positioned by removing the bumper. Anybody have experience with this? Thanks in advance.

You can remove the header panel, install your replacement filler, and then reinstall the header panel. When doing this, maneuver the header so these tabs notch under the bumper.