A very common misconception is that the burb and panel rear bumpers are identical to the front bumpers.
I have done some research over the years and I found that the rear bumpers on the burbs & panels are NOT identical to the front bumpers.
They are rounded on the ends like a front bumper but when you lay an ORIGINAL burb or panel rear bumper next to a front bumper you can see that they do not have as much of an arc.
Close but no cigar.