I'll take look tomorrow, but I know there's no inserts. If I remember correctly, the studs on the grill, go through, but there are thin foam type gaskets, that prevent metal to metal contact. The slotted holes give you room, to align the grill, to fit properly. Going on memory, as we're out for our Saturday night date, after Church, and enjoying pizza, & a pitcher...I should have taken pictures as I disassembled. Do the slots pictured take some type of insert? 1963 Polara.
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