Everything mentioned above is exactly right. Mine also started to tear. The holes for the bolts onto the wheel well need to be reinforced to handle the vibrations !!!
One other thing. Om the TD42 motor your exhaust is sitting very close to the battery, and batteries don't like heat. On mine I have branches and a turbo so don't have the heat shield like you do, but even with the heat shield that battery will get hot. While you are busy with the tray, make 2 sides to the tray, one on the exhaust side and one on the side closest to the firewall. You can leave the front open to allow airflow from the front. This will make a HUGE difference.
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