There are a couple issues with the repop crossmembers ...
The main one is the top lip or flange is half the width of the original. Won't be an issue for you since you're replacing all the sheet metal BUT if you were only replacing that piece, it wouldn't cover the holes made when you drill out the original spot welds.
Next big issue is the piece lacks the "dipples" along the top where it overlaps the ends if the frame. This prevents the whole piece from sitting up flush to the rest of the trunk pan.
I thought I had some photos of the mods I had to make but I can't find them but its the area I have circled.
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