on the top corner 90 degrees those are a part of the sides and held down by a single Phillips screw at top_ under_ the top trim piece. Top trim piece held on by metals clips, prys off, I used plastic benders from a vinyl wrap kit or body panels.I've had my trim in the garage for 10 years now. I need to install it. How do those corner 90 degree pieces come off?
the bottom corners fit inside of the bottom trim piece and in a perfect planet the bottom trim piece and both side pieces are in stalled simultaneously. What you have to do is get you side alignment up/down correct on eac side before assembly and then assemble your side pieces from top down while working them into the bottom trim... while seating the bottom trim. It took we three tries, the black bottom trim studs will snap out of the trim if too much pressure, start over, reassemble from top down while working in the sides.