1965 barracuda spare tire cover question

I think I’m going to go with the 1/4 plywood since I have some on hand. I’ll waterproof it. Does the board touch the inside quarter panels?
It's 1/8 inch Masonite (same material the front kick panels were made of)...
1/4 is Too Thick... just saying... 1/8 Masonite is Very inexpensive at Home Depot .. etc.
This is the panel directly over the spare tire... is this the one you mean??
Note: this is out of my 65 Barracuda Formula S that came with 14 inch wheels...

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Or is the compartment fold down panel you are wanting ?
This would be 1/2 inch thick plywood...

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