While I cannot speak specifically to the lower grill I know for a fact that the larger, upper grill does a fine job of holding itself together when removed from its frame.
If you think about it there is no way that screen would be usable if it was prone to self-destruct prior to being welded into place.
I suggest carefully cutting the weld points that currently hold your grill in place.
Please let us know your results.
Good luck.
Larry
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