Thank you for your question.
Depending on how well the aluminum foil melted and fused to the floor, you may not be able to remove the remaining aluminum foil. You could carefully try to scrape it off using a non metallic scrapper. The remaining aluminum foil will not cause any harm other than the looks of foil stuck on the bottom. The oven bottom is removable and replaceable. The oven bottom should have two thumb screws located at the rear of the oven floor. Remove the two screws, lift the rear up and then slide the front lip of the oven floor out from under the lip of the oven cavity and remove the floor.
I have checked and the part number for the floor is 316505601 and cost $68.76.
Please reply below if you need further assistance.
Here is a link to order floor if you would like.
Sears Parts Direct
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